Over a quaint area of land, shrouded by fog, a lone herder guides his sheep to pasture as a gigantic, metallic structure moves on four spindly legs into the highlands where the cloud cover quickly consumes it.
In a nearby city, young Sophie (English: Emily Mortimer Japanese: Chieko Baishô) sits at her window sewing adornments on a hat. Her boss enters and tells her the store is closing before inviting her out. Sophie politely declines. Some of her coworkers chatter excitedly and point outside. Sophie looks and sees the metallic object vanishing in the far off hills. The so-called 'castle', as the girls call it, belongs to a reclusive wizard named Howl (English: Christian Bale Japanese: Takuya Kimura) who is reputed to steal the hearts of beautiful young women. The girls joke about whether they will be preyed upon as they leave. Sophie finishes her hat and exits the store alone.
She takes a trolley downtown and decides to cut through an alleyway since a parade of soldiers is moving down the main street. As she appears to look for a particular address, she bumps into a couple of soldiers who begin to flirt with her. Sophie explains that her sister is waiting for her, but the soldiers refuse to let her leave. She then backs up into a handsome young man who drapes his arm around her, claiming to have been looking for her. With a quick gesture, he forces the soldiers into a straight stance and sends them marching down the alley. He then offers to escort Sophie wherever she needs to go and tells her not to be alarmed, but he's being followed. As they walk down the alley, a number of globular shadows appear out of the walls and begin to rush towards them. The mysterious man apologizes for getting Sophie involved and, as the shadows are about to merge on them, puts his arm around her waist before leaping high into the air. As they hover above the rooftops, he instructs her to start walking. They step through the air together and the man sets Sophie down on the balcony of her sister's bakery. He tells her he will draw off their pursuers and that she should wait a bit before going outside again, and then leaves.
Downstairs, Sophie's sister, Lettie (Jena Malone), is told of her arrival. She rushes upstairs to tell Sophie that she was seen floating onto the balcony with a strange man. Sophie recalls the experience as if it was a dream and later explains to Lettie that the man must have been a wizard. Lettie advises her on the dangers of trusting wizards and that, if it had been Howl, he would have surely stolen her heart. Melancholy, Sophie notes that Howl only preys upon 'pretty' girls. Lettie resigns to this statement and warns Sophie to be careful, regardless, and that even the Witch of the Wastes (English: Lauren Bacall Japanese: Akihiro Miwa) is on the move.
Lettie asks if Sophie will spend the rest of her life in the hat shop, but Sophie reminds her that the store was important to their father. Lettie tells Sophie that she should live her own life before Sophie leaves.
Sophie arrives back at the hat shop and locks the door behind her but, as she's putting her hat away, a large and elegant woman enters through the door. Sophie tells her the shop is closed but the woman ignores her and insults the shop, calling it tacky. Growing angry, Sophie once again asks the woman to leave but is reprimanded for standing up to the Witch of the Wastes. Before she can react, the Witch flies towards Sophie and flows over her like a windswept fabric, covering her in dark magic. The Witch glides back to the door and asks Sophie to give her regards to Howl before closing the door behind her. She leaves quickly in a sedan chair carried by two Shadow Men; the same globular figures that pursued Sophie earlier.
When Sophie finally looks up, she is horrified to discover that shes been aged into an elderly woman. She struggles to stay calm despite her haggard appearance. The next morning, her mother (English: Mari Devon) arrives at the shop to hear that Sophie is locked in her room, apparently ill. When she leaves, Sophie gets up and tries to motivate herself; accepting that now, at least, her clothes are appropriate for her age and decides that can't stay at the shop. She packs a few things and leaves town, catching conversation on the streets that the prince of another country has gone missing and that war is imminent.
Sophie hitches a ride out of town and heads for the mountains, despite the driver's warning that there's nothing out there but witches and wizards. After a while she takes a rest to eat the food she's packed and notices a stick protruding out of a nearby bush. Deciding it will make a nice walking cane, she yanks it out with some force and realizes that its a scarecrow which is somehow standing on its own. She names it Turnip-head before strolling away. Turnip-head follows Sophie, hopping along on its pole, despite her objections to having dealt with enough magic for the day. As the sky grows darker and the wind picks up, Sophie struggles up the hillside. Turnip-head fetches a walking stick for her which she gratefully accepts before asking if there is a place where she can find shelter. Turnip-head bounces away and Sophie muses to herself how clever she's gotten to have convinced him to leave.
However, Turnip-head soon returns, to Sophie's shock, with Howl's Castle close behind. Though it is the last thing Sophie was thinking of when she asked for shelter, she discovers a back door hanging from the rear of the castle as it walks over her. She runs for the door and is allowed entry.
Nothing stirs within and there is no light save for a single fire set on a large hearth. Sophie sits herself down on a chair in front of the fire, commenting how the place is less like a castle and more like a living room overstuffed with junk. Still, in her old age she realizes nothing scares her anymore and begins to doze off. Suddenly, the fire in front of her conjures eyes and notes that Sophie has quite a curse on her. It introduces itself as a powerful fire demon named Calcifer (English: Billy Crystal Japanese: Tatsuya Gashûin) and offers to relieve Sophie's curse if she helps him with his. Sophie asks if he can be trusted and denies his proposal but he pleads with her and claims that his master, Howl, keeps him under a tight regimen. Falling asleep, Sophie relents and agrees to help him though, as he watches her, Calcifer doubts her ability.
In a bayside town, two officials approach a building and knock on the door. The sound awakens Sophie who looks to the door with some confusion before a young boy comes down the stairs. Sophie feigns sleep again as the boy approaches and Calcifer mentions the knock came from the Porthaven door. The boy, Markl (English: Josh Hutcherson Japanese: Ryûnosuke Kamiki), dons a magical disguise that makes him appear like an old man and answers the door after turning a color-coded knob. Sophie looks over curiously and is amazed to see that the door has opened to a new area. The officials at the door ask for the Wizard Jenkins and inform Markl that he's been summoned to lend his magical assistance to the war effort. Markl accepts the notice and shuts the door before addressing Sophie who's giving Calcifer fresh wood. She tells Markl that Calcifer allowed her inside but Calcifer objects, saying she simply wandered in from the wastes.
Markl wonders aloud if Sophie is a witch but a knock at the door draws his attention away. He opens it to help a young customer who asks if Sophie is a witch. Sophie responds that she's the scariest witch of them all before the customer is sent off with her potion. Markl tells Sophie not to lie to customers and, when she points out his own disguise, informs her that he needs to practice his magic. When another knock sounds on the door, Markl opens the door to reveal the capital city of Kingsbury where another pair of officials requests the assistance of the Wizard Pendragon. Amazed, Sophie tries the knob out for herself, finding that each color represents a different location. When she asks about a fourth, black setting on the wheel, Markl says that only Howl knows where it leads.
Markl begins to make breakfast for himself and Sophie notices a basket of eggs and bacon. She offers to make something for him but he explains that Calcifer only obeys Howl. However, Sophie manages to force Calcifer into obedience by threatening to dump water on him or, worse, tell Howl of their secret agreement. Calcifer reluctantly agrees to obey and cook the food while Markl, amazed at Sophie's willpower, fetches a kettle to boil tea. The knob beside the door turns to the black setting and the handsome stranger Sophie met the day before walks in. Sophie is startled when Markl addresses him as Master Howl and tries to calmly continue cooking before introducing herself as his new cleaning lady, hired by Calcifer. Howl gently pushes her aside and takes over the cooking, feeding the eggshells to Calcifer. The three then sit down to eat and Howl asks Sophie what she has in her pocket. She reaches in and is surprised to find a red note hidden there. She hands it to Howl and, as it touches his fingers, the note bursts into flame and burns an inscription on the table from the Witch of the Wastes. The encrypted message reads that Howl's heart will soon belong to her. Howl rubs the message off the table, looking pained as he does so, before feeding Calcifer his breakfast and instructing him to heat hot water for his bath and move the castle further to the west. He then heads for the door, calling back to Sophie not to get too carried away cleaning, and leaves through the black portal.
Markl questions if Sophie is working for the Witch of the Wastes, but Sophie angrily denies it, her mouth abruptly sealing shut before she can utter a word about her curse, and promises to throttle the witch the next time she sees her. She orders Markl to finish his breakfast and furiously begins cleaning. Markl does his best to move extra things outside and warns customers to return later as there is a 'witch on the rampage inside'. Having cleaned most of the room, Sophie goes to remove the ashes from the hearth while Calcifer warns her that he may go out. She ignores his whining and moves the last bit of wood to hang over a pot with Calcifer clinging to it, his round lower half dangling. As she takes the ashes outside, Calcifer falls and smolders in the pot. When Sophie comes back inside she sees Howl standing over the hearth, encouraging Calcifer to reignite on new logs of wood. He calmly advises her not to torment his friend before leaving once again. Sophie goes upstairs to clean and tells Markl to put away whatever he doesn't want thrown out. After noticing the particularly dirty bathroom, Sophie sees the castle moving outside. She walks out onto a balcony, standing a bit straighter, and admires the high view of the countryside. She calls down to Calcifer, complimenting him on his spark which pleases him greatly. Markl joins Sophie outside and notices a long pole sticking out of one of the castles recesses. Recognizing it, Sophie pulls Turnip-head out of the hole. He regains his stance and bounces on the roof of the castle. Markl asks Sophie if she is, indeed, a witch to which she responds that she's the worst kind; the kind that cleans.
Later, Calcifer sets the castle down by a mountain lake and Markl and Turnip-head help Sophie string out the laundry. Markl suggests that Turnip-head is a demon but Sophie says that, if that's true, he must be a good demon since he led her here. She sits by the side of the lake and sighs to Markl that she's never felt more at peace.
Meanwhile, Howl flies in a bird-like form over a fiery landscape, watching as large airships drop bombs. A number of menacing winged creatures fly towards him but he swiftly eludes them and escapes through a break in the clouds, sealing it shut behind him.
Back at the castle, the door opens and Howl walks through, his wings drooping and his feathers scorched. He sits in the chair in front of Calcifer's hearth and, with difficulty, transforms back into his human self. Calcifer warns him that, if he continues to transform, it will be harder to become human again but cheerfully shows Howl the extra firewood Sophie left for him. Howl admits that the war is getting worse and other wizards have been recruited to fight, most having gotten to the point where they can't remember being human. He asks Calcifer to heat water for his bath and stops by a curtain drawn to the side of the room. He pulls it back to see Sophie sleeping in her youthful form and considers her a moment before going upstairs. The sound of the water running awakens Sophie, once again elderly.
That day, Sophie and Markl walk to the Porthaven market to buy food. Near the harbor, a crowd of people suddenly comes together as a battle-ravaged ship arrives at port. Sophie urges Markl to leave as she notices a shadow man scouring the crowd. An enemy airship flies overhead, dropping bombs into the harbor and sending leaflets of propaganda falling to the ground. Sophie and Markl rush back to Wizard Jenkins' shop and shut the door. Suddenly, Howl comes running down the stairs with a towel wrapped around his waist, howling and clutching his hair, turned from blonde to a vivid red. He yells at Sophie for getting carried away and ruining his bath potions. She defends herself, saying she merely moved things about but Howl is inconsolable. He sits down and moans that he looks hideous, turning his hair black and saying that there's no point to living if he can't be beautiful. The room begins to shake and shadows stretch. Markl says that Howl is summoning spirits of darkness and did this once when a girl dumped him.
When Sophie tries to comfort him, Howl's body begins to excrete ooze. Nervous and growing upset, Sophie yells at him that she's never felt beautiful in her life and runs outside into the Wastes where she begins to cry in the rain. Turnip-head approaches her with an umbrella which cheers her up and Markl runs out to get her. Sophie goes back inside to find Howl slumped over the hearth, his ooze threatening to extinguish Calcifer, and tells a worried Markl that he's just throwing a tantrum. Sophie helps him up and carts him upstairs where she instructs Markl to clean him.
Howl is put to bed and rests as Sophie comes in, offering him some warm milk, which he silently refuses. As she gets up to leave, Howl asks her to stay. He explains that the Witch of the Wastes is looking for him and admits that he's a coward for hiding, which is what most of his magic is put towards. When Sophie inquires, Howl says that, at one time, the Witch was very beautiful and Howl decided to pursue her only to find out that she really wasn't. So he ran away. Sophie sighs in exasperation and Howl says that he knows he can't hide for much longer now that both of his pseudonyms have been summoned to the palace to serve in the war effort. The oath he swore in the Royal Sorcery Academy requires him to answer the summons. Howl claims that the war is folly and asserts that Sophie doesn't understand how these people are despite her belief that the king should know what his subjects think.
Suddenly, Howl sits up and proposes that Sophie go to the palace in Kingsbury, pretending to be Pendragon's mother, and convince the king that Howl is of no use to him. Sophie reluctantly agrees. She puts on her hat and Howl uses his magic to bring some color back into her dress. Before she leaves, he gives her a ring to wear that he says will guarantee her safety and promises to follow her in disguise. Though Sophie is skeptical of the plan's success, she tries to figure what kind of disguise Howl may take as she walks towards the palace. She figures a pigeon or a crow would be too flamboyant but, as a small plane flies by with a young lady giggling beside her pilot, Sophie muses the pilot could be Howl. As she continues, she's soon accompanied by a small dog (Daijirô Harada). She asks if it's Howl and takes its weak bark as confirmation.
As she approaches the steps to the palace, two shadow men carrying the Witch of the Wastes' sedan chair come up beside her. The Witch peeks out and thanks Sophie for delivering her note and asks how Howl is. Sophie replies curtly that Howl has been a big baby since she started work for him, so she's come to the palace to request another job. The Witch brags that she's been summoned for her skills in magic and is going to see Madam Suliman (Blythe Danner Japanese: Haruko Katô), the king's sorcerer, who has finally seen what talent the Witch has. Sophie asks, if the Witch is so talented, why she doesn't remove her curse. The Witch responds that she only casts spells and cannot break them, leaving Sophie irritated.
As the shadow men approach the steps to the palace, they trigger a spell which renders them useless. A guard announces that the Witch must continue on foot which she does with frustration. Sophie soon catches up to her but finds that she must carry the dog up the high stairs. Though struggling, she manages to pass the Witch as she trundles upward, sweating profusely. Sophie makes it to the top and asks the Witch why she doesn't just give up, but the Witch refuses saying that she's waited 50 years for a summon since Suliman banished her to the Wastes. By the time the Witch makes it up, she's terribly disheveled and Sophie notes that she looks older. They walk into a lobby together, with the dog in tow, where a lone chair sits. The Witch claims it and sits down, relieved, while Sophie is led into a side passage. Large bulbs around the lobby suddenly light up, casting long shadows on the Witch, forming dark figures. The Witch cries out as they move around her in a circle.
The dog leads Sophie into a large greenhouse where she is introduced to Madam Suliman, seated in a wheelchair. Sophie is surprised to see the dog lie beside Suliman and inquires about him. Suliman tells her his name is Hin, her personal errand dog sent out to escort her. Sophie sighs heavily but keeps to the original story, claiming to be Howl's mother and explaining that he would be rather useless. Suliman is saddened by this news and says that Howl was her last and brightest student until his heart was stolen by a demon. Since then, he's been using his magic for purely selfish reasons and Suliman warns Sophie that, should he continue living as such, he will end up as the Witch of the Wastes. Upon her cue, the Witch is brought in on a dolly, reduced to her normal state as an old woman and deprived of magic. Suliman threatens to force Howl's magic from him if he refuses to honor the summon.
Sophie stands and says that she understands now why Howl refused to come; Suliman's summon was merely a trap to strip him of his powers. She asserts that Howl may be selfish, but his intentions are pure and he only wants to be free. As she speaks, her appearance gradually fades back to her youthful look. Suliman smiles and says that Sophie is in love with Howl. The statement causes Sophie to recoil and revert back into an old woman. The Witch grabs Sophie's dress, asking for Howl and, though Sophie claims he's not coming, Suliman says that he should, now that she knows his weakness.
A propeller craft lands in the grass outside and a tall man climbs off and enters the greenhouse. Suliman addresses him as Majesty and introduces him to Sophie as Howl's mother. The King declares to Suliman that he's decided against using magic to win the war since Suliman's powers shield the palace rather than protecting civilians; a statement that Suliman ironically compliments. At the opposite end of the room, a second King enters, shouting that he's come up with a new battle strategy. When he sees his copy, the real King laughs and praises Suliman on her tricks before leaving. Still smiling, Suliman greets Howl who removes his disguise and grasps Sophie, saying that he's fulfilled his oath and must be leaving. Suliman says she won't allow it and conjures a wave of water to flood the room. The group is transported to an empty realm where the earth appears miles below them. Howl tells Sophie not to look down as the Witch clings to her dress. Suliman appears above them and tells Sophie she's going to show her what Howl truly is. Falling stars surround them and begin to encircle Howl and Sophie, chanting. Howl is painfully forced to transform into his bird state and attempts to attack Suliman before Sophie stops him. Suliman raises her staff and throws it, but Howl leaps up and breaks through the illusion out of the greenhouse. He drops down onto the propeller craft with Sophie and the Witch lands in the back seat. Hin leaps onto the craft and puts himself in the Witch's lap as they fly off.
Sophie sneers at Hin but decides that they are now too high to dump him as Howl gives her the controls to the aircraft. She struggles to maintain flight but soon gains a handle on it, despite nearly crashing. She asks Howl why he bothered to make her go to the palace if he was going. He responds that he's terrified of Suliman, but Sophie's courage gave him the strength to face her. Seeing that they're being followed by the King's men, Howl tells Sophie he will give her five minutes of invisibility and that her ring will guide her back to the castle. All she needs to do is summon Calcifer. He then separates from the aircraft on a copy to ward off their pursuers.
At the palace, Suliman's wards pull her staff from the chair where Sophie had been sitting and she exclaims that was the most fun she's had in a while. She sends out troops to the shops of both Pendragon and the Wizard Jenkins but, when they break down the doors, they find empty buildings. Meanwhile, Sophie continues to fly in the rain. She passes over her hometown and navigates back into the mountain Wastes. The Witch, holding onto Hin, comments that he is a 'nice doggy' but Sophie refuses to trust him. Up ahead, she sees the castle waiting for them but, unsure of how to land the craft, flies into the castle's mouth where they crash. However, unharmed, they all climb out of the wreckage and Sophie greets Markl.
That night while everyone sleeps, Howl enters the room, hunched over and semi-transparent. Calcifer warns him that he's gone too far before Howl goes upstairs. Sophie wakes, somehow returned to her youth, and notices Howl's footprints on the floor surrounded by feathers. As she picks one up, it dissolves. Worried, she puts on a pair of boots and takes a candle. The footprints on the stairs appear bloodied but Sophie follows them. She walks into Howl's room and finds that it has transformed into a vast tunnel, the walls glittering with his toys and adornments. She follows the tunnel until she comes upon Howl, breathing heavily and curled up in his bird-form. He tells her to go away but she refuses and tells him that she can help him break his curse. He says that she can't even break the one on her and Sophie tells him she loves him. Claiming she's too late, Howl stands, revealing a disfigured face full of sharp teeth and flies away, leaving Sophie calling for him, once again an old woman.
Sophie suddenly awakens and hears the bath water running. She asks Calcifer if Howl is back and he replies that she needs to hurry to break their curse; Howl is getting worse. Frustrated, Sophie asks if Howl is really a monster. Calcifer can't answer any details but reveals that if he is extinguished, Howl will die too. Later, Markl and Turnip-head pitch in to help Sophie remove the propeller plane from the wall of the castle. Once the blockage is cleared, Howl comes down the stairs, looking cheery. Upon seeing Turnip-head, he detects a strong spell on him too and says that it seems everyone in their growing family has problems. He draws a large chalk circle with magical symbols on the ground outside and instructs Calcifer to move the castle over it. He then draws a smaller copy inside and takes Calcifer off the hearth with a shovel. He stands over the circle and Calcifer uses his demon powers to help Howl reconfigure the room. When all is done, Howl shows Sophie the new additions including her own room which looks exactly like the one in her hometown above the hat shop. Outside their door is a courtyard that leads to a new flower shop that Sophie can manage. Seeing everything, she becomes youthful again and is touched by Howl's kindness; though he merely wants everyone to live comfortably. He shows her a new doorway on the color turn-knob that leads to a field covered in flowers. A lone cottage stands near a stream and Howl explains that it used to belong to his uncle, a powerful wizard, who gave it to him so that he could study sorcery in peace. Now, he's giving it to Sophie.
Fearful that he is leaving, Sophie begs him to stay and says that she wants to help him, even if she's not talented or pretty. When Howl assures her that she's beautiful, she becomes old again. Suddenly, a large warship passes over them. Angered by its presence, Howl lightly gestures and causes the ship to malfunction. This display of magic causes his arm to painfully transform and feather, though Howl tries to hide it. When the airship yields flying creatures, Howl grabs Sophie and sprouts wings, carrying her back to the door to the castle. He drops her inside and flies away. Markl and Hin find Sophie on the stairway by the door exclaiming that she's too old for these shenanigans. That night, before bed, Markl tells Sophie not to worry about Howl; he's often away for days at a time, as Sophie puts the Witch to bed. Before she can leave, the Witch tells Sophie she knows she's in love and her sighing has given her away. Sophie asks the Witch if she has ever fallen in love, to which the Witch gleefully replies that she still is and simply can't ignore the hearts of handsome young men. An air raid siren sounds outside and the Witch warns Sophie not to go out; Sulimans henchmen are no doubt looking for the house although Calcifer keeps the place well hidden.
The next day, after returning from market, Markl rushes into the courtyard and tells Sophie that a strange woman has followed him inside. Sophie looks up to see her mother who rushes forward in tears, crying that she's been looking everywhere for her. Sophie invites her in and her mother reveals that she's gotten married again. She sets a small bag on a table that the Witch, sitting nearby, quickly notices. When Sophie and her mother go into the courtyard again, the Witch takes the bag and grabs a peeping bug that Suliman must have stored in there to spy on Howl. She feeds it to Calcifer who belches sickly. The Witch finds a cigar within the bag and begins to smoke it, much to Hin's disgust. Sophie's mother invites her to live with her but Sophie politely refuses, claiming to be happy where she is. She says farewell to her mother who leaves with a chauffer. As they drive off, she tells the driver that she did as she was told and must now return to her husband. She whispers for Sophie to forgive her. Sophie goes back into the castle where Markl tells her that he loves her and doesn't want her to leave. Sophie assures him that she will stay; they are a family.
That evening, Sophie attempts to reignite Calcifer who has weakened due to the cigar smoke. Markl goes to open a window but the Witch warns against it, saying that there's an air raid and Calcifer is too weak to properly protect the house. As Sophie goes to pull Markl back from the window, a series of bombs hits the side streets, sending a tremor through the house. Sophie runs outside to see most of the street enveloped in flames and a horde of Suliman's blob men approaching her. She runs back to the courtyard and looks up in time to see a bomb plummeting towards her, with Howl holding onto it. The bomb hits the center of the courtyard but fails to explode. Sophie runs to Howl who apologizes for not arriving sooner and escorts Sophie back into the house. Howl calls up Calcifer, coughing back to life, and takes the cigar from the Witch who says that she needs to have a chat at some point with Howl. He tells Sophie to wait at the house while he goes to deflect the second wave of bombs but she begs him to stay. He tells her he's tired of running and now has something that he wants to protect (Sophie) before flying out the door and into the ember filled sky.
Sophie retreats inside from the shadow blobs and changes the knob beside the door to return to the Wastes. She then goes outside to watch the battle and sees Howl attacking an airship, now more monstrous than human. She watches in horror as the ship goes down and explodes in a fireball. Sophie demands that Calcifer do something, but he can't change the portals without Howl's help. Sophie begs him to try so that Howl won't have a reason to fight for the shop and states that their vulnerability won't change no matter where they are. They come up with an idea. Markl and Turnip-head help the Witch leave the house and Sophie places Calcifer on a shovel. She backs out of the house with him and watches as the entire castle falls apart. They all go back inside and Sophie puts Calcifer on the hearth, ordering him to move what little is left of the castle closer to Howl so they can help him. However, he is too weak and asks Sophie to give him something of hers. She offers him her long braid and he eats it, gaining strength enough to put together a wobbly, smaller version of the castle. Sophie commends his powers and Calcifer quips her on what he could have done with her eyes or her heart.
At this, the Witch suddenly realizes that Calcifer has Howl's heart. Blindly motivated by her crush, she takes Calcifer off the hearth and holds the heart close to her. The castle shakes and stumbles and the Witch is set on fire, crying out in the heat. Calcifer yells out as his powers are stripped and Sophie tries to take him from the Witch but she refuses to let go. In her panic, Sophie throws water over them which extinguishes the fire. Then, the section of castle Sophie is standing on breaks away from the rest. Hin leaps into her arms as they fall into a deep chasm, Markl calling after her while the castle continues on its way across the mountains.
Sophie wakes up, having survived the wreck, and is approached by Hin. She bursts out crying, wondering if she killed Howl by pouring water over Calcifer. She buries her face in her hands as the ring Howl gave her begins to tremble, a single beam of light shining from it. Sophie asks the ring if Howl is still alive and it points to the main door that had fallen away, propped against a wall of dirt. She opens it, finding a looming darkness ahead and walks through, Hin following. Sophie finds herself in Howl's cottage and walks outside to the fields where she sees a young boy watching a shower of falling stars; each one perishing as it lands. Realizing the doorway was a portal to Howl's childhood, Sophie runs towards the young Howl and watches as he catches a star, speak to it, and swallow it. He coughs and brings forth from his chest a beating flame; Calcifer. The ring on Sophie's finger breaks and Sophie is plunged into a deep darkness, but manages to shout out to Howl, telling him that she can help him and to find her in the future.
Sophie and Hin make it back through the doorway where they find Howl waiting for her, nearly a complete form of a monstrous bird. Sophie approaches him, brushes the feathers from his face and kisses him, apologizing for taking so long. She asks him to take them to Calcifer and, as she stands on his clawed foot, Howl takes off. They arrive at the walking castle where Markl, the Witch, and Turnip-head are waiting; the castle having been reduced to two walking legs supporting a single piece of floor. As soon as they arrive, Howl collapses and the feathers disintegrate to reveal his human body. Sophie props him up before going to the Witch and begging her to release Calcifer. Though she refuses at first, with Sophie's plea, she finally relinquishes him to her. Calcifer tells Sophie he's very tired but may be all right if Sophie is the one to give Howl his heart back. She presses him into Howl's chest. A light bursts from it and Calcifer, once again a star, flies off shouting that he's free.
With Calcifer gone, the castle stops moving and begins to tip over. The legs fall apart and the flooring slides quickly down the mountainside. Turnip-head leaps ahead of the floorboard and uses his pole to slow it down, but splinters and grinds it down to near nothing. The floorboard finally stops, propped between two rocks. Proud by his sacrifice, Sophie kisses Turnip-head which suddenly causes him to vibrate and transform into a human. He bows to Sophie and proclaims that he's the prince (English: Crispin Freeman Japanese: Yô Ôizumi) from the neighboring country who had gone missing. A spell had turned him into a scarecrow and a kiss from his true love was the only thing that could break it.
The Witch compliments the handsome young man as Howl awakens and complains of a weight on his chest. Sophie tells him that a heart is a heavy burden and, when he looks at her and likens her hair to starlight, hugs him fiercely. The Witch tells the prince that, though his love is in love with someone else, he should still go home and put an end to the war. He agrees to do this, saying that even hearts can change, and the Witch suggests that she'll be waiting for him should he return. As the prince leaves, Hin sends a visual message to Suliman who asks him where he's been. As he shows her, she begrudgingly calls him a traitor and watches as he rejoins Sophie and Howl. She admits that her fun is at an end and decides to finally put a stop to the war.
Calcifer returns to Sophie and ignites into a flame, telling her that he's missed them. Sophie kisses him as well and Howl creates a new, flying home for them all to live in. The Witch sits in the courtyard while Markl and Hin play and Sophie and Howl stand together at the bow of the castle and share a tender kiss.