New York, 1927
Notorious dark wizard Gellert Grindelwald (Johnny Depp) is being imprisoned by the American Ministry of Magic. MACUSA President Seraphina Picquery (Carmen Ejogo) oversees Grindelwald as he is being transferred to London with one of her employees, Abernathy (Kevin Guthrie). As they become airborne in a carriage pulled by Thestrals, it becomes apparent that Grindelwald and Abernathy have switched places, as Abernathy has always been loyal to Grindelwald. Abernathy fills the carriage with water while Grindelwald diverts the Thestrals' path. They kill two guards, while a third, Spielman (Wolf Roth), survives his fall. Grindelwald then proceeds to head out and find the rest of his followers.
Newt Scamander (Eddie Redmayne) is being prepped for a hearing with the British Ministry of Magic. He meets with an old Hogwarts friend, Leta Lestrange (Zoe Kravitz), who is engaged to Newt's brother Theseus (Callum Turner), with whom Newt has a bit of a strained relationship. Newt enters the meeting to have his right to travel reinstated after the events that took place in New York when Newt's beasts were loose and the Obscurial Credence Barebone (Ezra Miller) wreaked havoc. Although Newt believed Credence to be dead, he is told that Credence is alive and has resurfaced in Paris. Newt is given a chance to get his travel rights back under the condition that he works under Theseus at the Ministry to help find Credence since they know that Grindelwald is trying to find him and lure him to his side, but Newt refuses to work with his brother. An Auror named Grimmson (Ingvar Eggert Sigurosson) takes on the task, though he appears to have sinister intentions.
Grindelwald and his followers meet in a private residence to discuss going off to find Credence. In another room next to them, they find a small boy who can't yet comprehend what is going on. Grindelwald has one of his followers, Carrow (Maja Bloom), use the Killing Curse on him.
Newt leaves the Minstry building and finds a glove tapping him and pointing at him to meet on top of a building. He grabs the glove and is apparated to meet with his former professor, the great Albus Dumbledore (Jude Law). They meet privately as Dumbledore also tasks Newt with going off to find Credence in Paris since he may be in danger or be a danger to others. He also leaves Newt with a card with an address for a safe house in Paris. Newt is reluctant to take on this mission, but Dumbledore informs him that it must be him since Dumbledore cannot move against Grindelwald.
Newt returns home to his assistant Bunty (Victoria Yeates), who has scrapes on her arm after handling his Kelpie (like a giant magic seahorse). After dealing with baby Nifflers and the Kelpie, he hears a noise coming from his room. To Newt's surprise, he finds Jacob Kowalski (Dan Fogler) and Queenie Goldstein (Alison Sudol) in his room, having apparated all the way from New York. Newt is surprised that Jacob remembers him despite being Obliviated, but Jacob explains that Queenie filled him in on the bad things. Newt is also disappointed to hear that Tina (Katherine Waterston) is not there and has been seeing another Auror after a mistake in a magazine led her to believe that Newt was engaged to Leta instead of Theseus. Newt quickly discovers that Queenie has enchanted Jacob to make him love her, and she reluctantly allows Newt to remove the enchantment. Although a bit displeased at being bewitched, Jacob follows Queenie as she leaves Newt's place to tell her she didn't need to use magic on him because he already loved her. However, they get into an argument due to the laws against magical folk being in relationships with muggles/no-majes. Queenie reads Jacob's mind and hears him call her crazy, so she leaves him. He returns to Newt's place and joins him as they head to Paris.
In Paris, we find Credence working at a freak show under the cruel ringmaster Skender (Olafur Dari Olafsson). Credence is close to Nagini (Claudia Kim), a young woman who is a Maledictus, meaning she is cursed to transform into a snake until one day when the transformation becomes permanent (she will later become Voldemort's pet snake). Skender puts on a show for people to have Nagini shapeshift for them, with Tina in attendance. Credence lets loose a bunch of small creatures that create sparks, leading to chaos in the tent. This allows Credence to get away with Nagini while Tina tries to contain the situation. Skender just takes everything with him and gets out. As Tina walks away, she is found by Yusuf Kama (William Nadylam), who was also in attendance at the show. He talks to Tina and tells her that he is looking for Credence. Yusuf tells Tina he is the last of a pure-blood line, as is Credence.
Grindelwald knows where Credence is headed, to find his birth mother. He plans to use the boy in eliminating Dumbledore.
Newt and Jacob take a Portkey to Paris since it's the only way Newt can travel out of the country discreetly. Once they get there, Newt uses a spell to detect Tina's last movements in the area so that he can trace her location, as well as Yusuf's. Meanwhile, Queenie is also in Paris to find Tina. She goes to the French Ministry of Magic for a lead, but gets no help. At the same time, Abernathy and another Grindelwald follower, Rosier (Poppy Corby-Tuech) are lurking in the same building. Queenie is outside the building and overhears Newt and Jacob walking by her. She attempts to follow them but is overwhelmed when she starts to hear everyone's thoughts. Queenie is then found by Rosier, who invites her to join her.
Credence and Nagini arrive at the home of Irma Dugard (Danielle Hugues), the woman Credence was led to believe is his mother. She turns out to only be the nurse who delivered Credence and wrote her name on the documents. Irma embraces Credence moments before they are found by Grimmson. He fires a blast that kills Irma. Credence becomes enraged and takes on his Obscurial form, attempting to attack Grimmson, but he shields himself from Credence's moves, though Credence still manages to destroy most of the house. Credence and Nagini get away, and Grimmson goes to report on what he saw to Grindelwald.
Newt and Jacob find Yusuf on the streets. They approach him and ask if he has seen Tina. Yusuf guides the two to a cell where he has imprisoned Tina, and does so with Newt and Jacob as well. Outside, a Zouwu (a large cat-like creature) is on the loose. The three manage to free themselves and subdue Yusuf so that Newt can go out and lure the Zouwu with a toy and keep him in his briefcase with the other fantastic beasts.
At Hogwarts, Dumbledore's Defense Against The Dark Arts class is interrupted by Torquil Travers (Derek Riddell) from the British Ministry. Dumbledore sends his students out with Professor McGonnagall (Fiona Glascott). Travers tasks Dumbledore with taking down Grindelwald. He knows that the two of them were once close like brothers, though Dumbledore states they were closer than that. When Dumbledore says he cannot fight Grindelwald, Travers tells him he can no longer teach DATDA. Dumbledore later finds the Mirror of Erised and sees himself and Grindelwald as younger men making an Unbreakable Vow.
We catch up with Leta and see a flashback from her days at Hogwarts (here played by Thea Lamb) where she was bullied by other students, so she in turn curses them in ways such as making a girl's mouth disappear. She and Newt (here played by Joshua Shea) were each other's only friends, and he would take the blame for her wrongdoings. While in Dumbledore's DATDA class, the students are handling a Boggart (the being that shows people what they fear most). It turns into a desk for Newt since his worst fear is working in an office, but for Leta, it turns into a white sheet holding something inside. Afterwards, Newt shows Leta a tree where he finds Bowtruckles that have come to trust him. Back in the present, Dumbledore finds Leta. She asks him if he considered her as bad as the others did. He says no, and she replies that he is the only one who didn't see her as such.
Rosier brings Queenie to the hideout where she comes face-to-face with Grindelwald. Although Queenie is prepared to defend herself against him, he calmly speaks to her and entices her when bringing up the matter of loving who she wants to love.
Newt, Tina, and Jacob take an unconscious Yusuf back to his place. Tina wants to question Yusuf since he might know the truth about Credence. They look into his eyes and see a parasite in there. Newt and Tina manage to pull it out. Tina plans to take back her information to the Ministry, appearing to still be agitated with Newt over not telling her about him and Leta. Newt explains the confusion from what she read. Just then, they look up at the sky and see what look like black drapes sweeping across the sky, indicating that Grindelwald is summoning his followers. Newt and Tina plan to go to the French Ministry to find a box that contains the truth about Credence, while Grindelwald finds Credence and Nagini to try and lure them to his side.
Jacob is left alone in the house where he meets the famed alchemist Nicolas Flamel (Brontis Jodorowsky). He shows Jacob a crystal ball where he sees the whereabouts of Credence and Queenie. Flamel tells Jacob that Queenie is going to be at a cemetery in Paris. As Jacob is heading out to leave, he notices that Yusuf is gone. Flamel then goes into his closet (where he just so happens to be keeping the Sorcerer's Stone) and takes out a book to talk to a woman named Eulalie Hicks (Jessica Williams), as he knows that Grindelwald is rallying his followers at the cemetery, and he fears there will be death.
Newt uses Polyjuice Potion to disguise himself as Theseus to get inside the Ministry. They enter the records room and also take a moment to almost express their mutual feelings for one another. Theseus spots Newt and goes after him and Tina. As they hide, they overhear Leta reading a note saying that Lestrange family records have been moved to their family tomb. Leta finds Newt and Tina, and the records keeper finds them and sics her Matagots (creepy panther-like beasts) after Leta tries to defend herself against them. Newt brings the Zouwu out and it helps them escape.
Newt, Tina, and Leta come across Credence, Nagini, and Yusuf. Yusuf reveals that he has been looking for Credence because he wants to kill him, as Yusuf's mother Laurena (Isaura Barbe-Brown) was taken against her will by Corvus Lestrange Sr (Keith Chanter) under the Imperius curse, who impregnated her with a child before she ultimately died. That child was Leta. Corvus Sr would go on to have another child, Corvus Jr, whom Yusuf believes Credence to be. However, Leta says that Corvus Jr is dead because she was the one who killed him. As a child, she was on a boat with Irma, and the baby Corvus would not stop crying. Leta switched him with a quiet, sleeping baby just before the ship started to sink. Leta was on one lifeboat with the other baby, while Corvus was on a different lifeboat that capsized, and he drowned as a result (this is the form that the Boggart took for Leta). Leta has lived with this guilt ever since.
As part of his plan, everyone heads to the cemetery where Grindelwald has gathered his followers and set up for Credence to go to him. Jacob finds Queenie, who invites him to join and watch what Grindelwald has to say. The dark wizard preaches about their supremacy over non-magic folks. He shows them future images of World War II to show just how flawed the non-magic community is and how they will only bring their own world into ruins. Theseus leads Ministry Aurors there to stop them, along with Newt, Tina, Yusuf, Leta, Flamel, and Travers. Grindelwald's followers get away just as he creates a Protego Diabolica spell that spreads a powerful blue flame with a dragon-like form to spread across Paris. Several wizards are killed in the fire as the Aurors attempt to stop it. Grindelwald calls for new followers to join him. Credence decides to join, despite Nagini trying to pull him away. Queenie does so as well, even trying to get Jacob to go with her, but he cannot bring himself to do so and watches as Queenie leaves with him. Leta appears to try and join Grindelwald, but she instead makes an attempt to kill him. Grindelwald ends up burning her to ashes, to the horror of Newt and Theseus. Grindelwald disapparates with Credence and Queenie. The Aurors then manage to stop the fire from spreading. Newt then embraces Theseus as they mourn Leta.
Newt takes a vial of blood that his Niffler nicked off of Grindelwald and brings it to Dumbledore at Hogwarts. It is the reason that Dumbledore cannot fight Grindelwald, as this is what their Unbreakable Vow was for. Dumbledore tells Newt that he may be able to destroy it.
Grindelwald brings Credence and Queenie to a new hideout. He tells Credence his true name: Aurelius Dumbledore, making him Albus's brother. Grindelwald tells Credence that only he can destroy Dumbledore. Credence then tests out the strength of his power by blasting the side of a mountain.