The film opens with footage of a real life disaster that occurred on January 15, 1905 in Norway. A rock slide occurred near Lodalen in Nordfjord that happened while the nearby town was asleep. The resulting tsunami killed 63 people. The wave was 40 meters high when it hit land. A similar accident years later causes the death of 40 people. Norway has over 300 registered unstable mountainsides. Narration notes it is only a matter of time before the next big rock slide happens.
A Norwegian mountain based town, Geiranger, is now threatened by the same problem. Its unstable mountainside, the Akernes, will eventually send seven million cubic meters of rock down, which will crash into the water, causing a massive tsunami wave.
A geologist, Kristian (Kristoffer Joner) drives in his car, eventually driving it on a large ferry boat that will take him over the water into town. He arrives home and greets his wife and children. His wife Idun (Ane Dahl Torp) is struggling to fix a leaky pipe and asks for a plumbers wrench. Kristian however gives her the wrong one, so his teenage son Sondre (Jonas Hoff Oftebro) finds the right one so she can fix the problem. Kristian shakes his head and says their new home wont have problems like that, giving her a kiss. Idun notes that their home they have now has soul. "Whats soul?" Julia (Edith Haagenrud-Sande), their eight-year-old daughter, asks. "Soul is some nonsense your mother believes in", Kristian playfully replies.
During dinner, Kristian hypes up their new apartment, noting the various technological perks including being able to lock and unlock their door using a phone app.
After dinner, Idun continues to pack up the kitchen. Kristian comes in and asks if he should get rid of some old shirts. Idun asks why and Kristian notes that he is getting a new job, a new home, a new life etc. Kristian then says hell forget moving and they'll stay in town but Idun vetoes that, saying they decided to go. Idun then playfully says he should get a new suit, and should wear only those. Also, he should get a haircut and be more presentable. Maybe Ill get more attention than that mountain, she notes playfully. Kristian then asks if she wants attention and takes her in his arms, plopping her on the kitchen counter. As they are about to fool around like teenagers, Sondre walks by and becomes disgusted. "Hey, not on the kitchen counter! We have to make food on that!" he exclaims which causes his parents to erupt into laughter.
The next day, Kristian heads into what will be one of his last days of work at the Early Warning Center which is 102.1 meters above sea level. He goes into the control and asks how the numbers are. The tech says they are within acceptable parameters.
Kristian has cake with his co-workers, who want to say goodbye to him and congratulate on his new job in the oil industry. They also playfully rib his need to triple check data to the point of paranoia.
Kristian begins to clean out his office. As he does so, he hears beeping from the control room. He ignores it for a moment but when the beeping continues, he goes to investigate. He sees his team looking at the numbers which has spiked drastically in the past couple hours. Ground water levels have shrunk several feet. They look at camera footage, but everything looks stable. Kristian's face gets scared as he maps out worst case scenarios. However, one of his co-workers snaps him out of his trance, telling him everything is fine and that he can go back to packing up his office.
Kristian is at home, looking at the numbers, concerned as his wife and daughter pack up the house. Julia comes in and is happy she got all her stuffed animals into one box. Sondre asks if a few of the boxes are ready to be moved and if his father will be helping. Idun says he will. Talking to her, Kristian says something weird happened with the groundwater levels during the day. However, Idun brushes his concerns off saying his job is done, and the mountain will be around for a thousand years. She tells him to help with the packing so the moving truck can be ready to go the following morning.
Kristian goes outside to throw some old papers in the dumpster. Near the water, he sees his son, listening to music sadly. He walks up to him and asks how Sondre is doing. Sondre confesses he doesn't want to move. He likes his home for its beauty and safety. Kristian comforts him but notes his mother and him made the tough choice for the family's sake. Sondre asks what happens after a few years in Stavanger, will they just move again? Sondre walks away, despondent, while Kristian sits and ponders how his career change affects his children.
As they finishing up packing, Kristian and his family are greeted by their neighbors who talk about the move. Idun mentions that Kristian and the kids will be going ahead of her while she still has to work for a few more days. Kristian looks up at the mountains foreboding. He just cant shake the feeling that something is deeply wrong.
Kristian drives with the kids to the ferry meeting point. He looks at the mountain again. He sees Sondre play a Jenga game on his phone and the pieces toppling down. Looking at some nearby rocks, he notices a bunch of water dripping through them. A bunch of cars honk behind as it is time to dock the cars on the boat. When Julia asks if he is going to drive, Kristian quickly turns the car around and goes back to his office. He walks in and tells his colleagues he has to show them something, his voice grave.
Meanwhile, Idun is on a bike, on her way to work. She works at the Hotel Geiranger, which is only 1.7 meters above sea level. She is greeted by her friend and co-worker Vibeke (Eili Harboe) who gently chides her for being late. As they begin to check in a bus load of newly arrived guests, Vibeke asks about Idun's family. Idun says they are already on the ferry.
Kristian briefs the team, saying he believes now that the sensors may have been severed due to the shifting of the rock layers. If that is true, and the seemingly disappeared groundwater is shifting between the rock layers, they could eventually collapse, which will make it impossible to give warning to the town. Though the team is somewhat skeptical, the idea of being wrong is too much to fathom so they immediately head out via a chopper to investigate the sensors.
Landing on the Eagles Nest Control Station, a base set in the mountains, 874.1 meters above sea level, near where they have set up their sensors, Kristian and one of his colleagues get out with gear. They suit up with climbing gear.
Back at the hotel, Idun gets a call from Sondre, learning they are still in town. Idun asks where they are.
Back at the mountain, Kristian and his teammate clip onto the safety rope and proceed to rappel down the mountain crevice where their equipment is set up. They turn on helmet cameras so the rest of the team can see what they see. They begin to travel through the narrow area, with Kristian checking sensor four while the other man checks sensor five. They begin to pull out long strands of wiring, only for the other man to show that his wires have been severed. Kristian pulls out his and realizes his too have been cut.
Back at the office, Kristian notes that wires were not cut naturally but by movements in the rocks. One of his colleagues says they will look into it by conducting more tests and drilling more holes. Kristian balks at that, asking if the man heard anything he has told them. He shows them a simulation of what will happen if the mountainside falls. An 80 meter wave will decimate the entire town within ten minutes time. The colleague asks if Kristian wants to start a panic and ruin the tourist season.
Kristian asks if they are not going to alert the town, what is to be done. The co-worker, Arvid (Fridtjov Saheim) compromises, saying they will go on Yellow Alert, which will entail longer shifts for the crews, and the round the clock surveillance of the mountain. Avrid notes all they found were some cut wires but otherwise have no other evidence that something is wrong with the mountain. Kristian apologizes for being so quick to start a panic, and seems convinced that they will take care of it. As he goes back to the car, he notices his kids are gone. They left a note saying they were tired of waiting and to call their mother.
Kristian arrives at the hotel. He curses himself, realizing Idun will kill him for this. He finds his kids in the lobby while Idun is at the desk, glaring at him with daggers in her eyes. She quietly berates him, saying he cant go work for hours and leave their children in the car, especially since he doesn't work there anymore. Kristian apologizes, saying he got a real bad feeling. Idun sighs and says they will try to leave town the next day. She says she will set the kids up in a room for the night, but Julia wants to sleep in their home and say goodbye to the house. Sondre elects to stay at the hotel with his mother, giving Vibeke a flirtatious glance. So Julia heads home with her father, while Idun stays at work with Sondre.
In the car, Julia asks her dad if mom and he are getting divorced. Kristian chuckles and says no. He tells Julia that he and Idun had a small fight and they will get over it, he hopes. "Thats life", Julia notes. "That's life! Kristian concurs, chuckling.
Back at the hotel, Idun shows her son his room. She warns him not to take alcohol from the mini bar and not look at the porn channels to his embarrassment.
Back at the house, Kristian finds an old mattress for Julia to sleep on and a chair for himself to sleep in. Later that night, he tucks her in. Kristian notes they didn't need a hotel. "This place has more soul", Julia says. "Yeah", Kristian replies agreeing, "It actually does."
Kristian goes into the kitchen and has a drink with a bottle of liquor given to him by his colleagues. He sits in his chair and watches his daughter sleep.
At the hotel, Idun gets a text from her husband apologizing for his actions. She smiles slightly, ready to forgive. Thinking about his fears, she pulls out a folder at her desk, which details evacuation plans in the event of a tsunami wave and flips through them, noting a particular route in the hotel.
Back at the Eagles Nest, two of his colleagues are on shift, keeping tabs. Jacob (Arthur Berning) asks Arvid about Kristian, asking if he thinks Kristian will stay with the oil industry long. Arvid says Kristian will be back within a year as the mountains become an obsession for men like them.
As night falls, the town is quiet, especially at the hotel. Sondre is in his room, flipping channels. Bored, he grabs his skateboard and leaves, seeing Vibeke on the way out, saying hello. They trade glances at each other and smile. Walking down some stairs, Sondre finds a door that leads a basement level. He turns on his music and skates around the hallways.
Back at the base, one of Kristian's colleagues, Georg (Herman Bernhoft) is watching the horror movie 'Cold Prey' on his laptop. In the background, the computer starts to beep, showing a shift in numbers. Georg doesn't notice it until he accidentally knocks over a glass of milk. Noticing the numbers, he panics and wakes up Margot (Laila Goody).
Back at his house, Kristian wakes up after dozing off.
At the Eagles Nest, Arvid is awakened by the radio. Margot and Georg tell him that sensors say that the crevice has contracted. Arvid thinks that is impossible and tells them to re-calibrate the system and take another reading. He tells Margot he and Jacob will go down and check it out personally.
Kristian goes out to his porch and looks out to the mountain in the distance.
Jacob and Avrid rappel down into the crevice and take a look. Jacob gets a call from Kristian and he asks if everything is okay. He learns about the crevice contracting and he learns Jacob and Arvid are checking it out. Margot says they will keep him posted. Kristian says okay but as he hangs up, he can only think of the worst.
Back in the crevice, the two are moving along when some rocks fall on them.
Back at the basic, seismic activity is being recording and other readings are beeping like crazy.
Kristian sees a large bird migration in the sky. Now he knows something is wrong and pulls his papers out of the garbage in a panic, spilling them out on the kitchen floor.
Jacob and Arvid check the sensors and confirm the contraction numbers. Jacob goes to check on a seventh sensor but unlatches himself from the safety harness.
Kristian reads the paperwork and realizes that an avalanche is going to occur. Kristian calls the base and they patch him into Arvid who tells him to get the hell out immediately. As Arvid and Jacob goes to leave, a bunch of rocks fall. A large stone catches Jacobs leg, trapping him. Arvid goes to free him as the groundwater levels go down to dangerous levels. As Arvid tries to reach Jacob, the crevice begins to crush inward. The other sensors go to code red. Kristian tells her to sound the alarm but she hesitates. Arvid then tells her to go to Red Alert and sound the alarm. Margot presses the button.
The alarm system reverberates through the entire town. Idun hears it and goes outside.
The rock slide inside the crevice stops and Arvid can finally meet Jacob. Arvid hears a sound and calmly clips his line to Jacob. When Jacob asks what he is doing, Arvid replies, "It won't hold both of us."
The rock slide begins in earnest and the ensuing rocks knock Arvid off the ledge to his death (he sacrificed himself for Jacob). Jacob screams his name in horror. The avalanche of rocks begins to hit the water, causing a massive wave to form.
Back at the base, a countdown begins on the computer screen. The town of Geiranger has just ten minutes before the wave will hit them. Kristian loses the call with Margot and his daughter wakes up. As tremor hit the house, Kristian hugs her tight and puts a ten minute countdown on his watch. At the hotel, Idun is met by Vibeke. Idun realizes that her husband was right and tells Vibeke they have ten minutes. She then tells her to warn every guest they have to leave NOW and to find the bus driver.
Kristian and Julia race out of the house and into their car and drive off. He calls Idun but she doesn't have her phone.
Idun knocks on every door to warn the guests. She calls Kristian and asks if Julia is okay. Kristian sees a family packing the car as he drives by. He quickly opens the car door, tells them they don't have time to pack and to leave immediately. Other families are shown quickly driving out of the town. As he continues to drive, he tells Idun they can make it to the hotel, but Idun vetoes his plan, telling his concern is getting their daughter to safety. Kristian asks if she and Sondre will be okay and she says yes. As he sits at a crossroad hesitating, Idun tells him to get to higher ground. Realizing he has no choice, he makes the turn that will take up the mountain road to higher ground.
The wave continues to make its way to the town, destroying everything in its path.
Idun meets Vibeke in the lobby, where a group of guests, including the driver are arguing with them over their luggage. Idun shuts them all up, explaining that if they don't get above 80 meters sea level in the next ten minutes, a mega-tsunami wave will kill them all. This convinces everyone who rushes to the bus. However, Idun realizes her son is missing and races to find him.
Back on the road, Kristian and Julia are caught in a major traffic jam. He checks his watches and sees they only have four and half minutes before the wave hits, yet they are only 47 meters above sea level. If they don't cover some serious ground soon, they will all die. He pulls Julia out of the car and tells her to run. As he passes every car, he tells the passengers to get out and run to higher ground. Everyone believes him and soon a large group is running up the hill to safety.
At the hotel, Idun goes to Sondre's room to find it empty. She calls his phone, but he doesn't pick up. She races back to the lobby where Vibeke is loading passengers on to the bus. Idun asks Vibeke about her son and Vibeke says she saw Sondre in the hallway earlier. Idun races back in unwilling to leave without her son. A woman, Maria (Mette Agnette Horn) part of a couple Idun was nice to earlier, leaves the bus to help her, her husband Phillip (Thomas Bo Larsen) reluctantly following. Vibeke screams that they won't make it.
Back on the hill, Kristian checks his watch, seeing they are only 57 meters up. He sees his neighbor Thomas and his family, telling them to get out of the car. However, another man exits his vehicle and it reverses, trapping Thomas wife Anna's leg. Kristian looks back and sees the wave is not far behind. Kristian tells Thomas to get their daughters to safety. Kristian gets in the car that trapped Anna and moves it, freeing her. However, the crushing has given her a terrible limp. As Kristian tries to move her, he realizes they won't make it to a safe distance in time. He quickly puts her in a car, and gets in the passenger side. He tells her to buckle up and hold on tight. With the wave seconds away, he and Anna hold hands tightly as the wave hits. The water crashes through the back window submerging them as they see and feel cars and other debris tumble around them. As they look through the windshield they scream underwater as a large piece of debris hits the windshield.
Back at the hotel, Idun and the couple call out for Sondre. Maria hears a noise, and notices the basement door. Idun races down and finds Sondre. As they races back to the lobby, they see the bus was forced to leave without them. Idun sees the massive wave about to crash into the town and screams there is a bomb shelter in the hotel (from the plan she noticed earlier) and pushes her son and the couple back inside. Maria freezes in shock with Idun having to break her out of it. They run in just as the wave hits the hotel, water following them quickly behind. Phillip and Sondre find the bomb shelter and open the door waiting for Idun and Maria. However, Marias hesitation has cost them precious seconds, as the water comes in right behind them and sweeps them off their feet. Idun manages to catch the door but Maria is sadly swept away in the water down the hallway. Phillip calls for his wife but Idun tells him sadly that shes gone and if he doesn't shut the bomb shelter door, they will all die. Idun and Sondre force the door close and find themselves in a half submerged room. The light inside sparks out and they are left in darkness.
Back on the hill, Kristian wakes up in the car upside down. He looks to Anna only to see she is not responsive. He puts his fingers to her neck and doesn't find a pulse. He realizes she is dead and there is nothing he can do. Kristian unlatches his seat belt and escapes the wreck, crawling out of the car. He takes a long look around, taking in the large swath of destruction. He calls out his daughters name and proceeds to climb the hill.
Back at the geology base, we see the computer simulation timer has reached zero, as Margot and Georg continue to monitor the reading. The radio cackles to life. It is Jacob. Margot asks if he is okay. Jacob breaks down in tears. Margot asks if Arvid is okay. Jacobs lack of response makes Margot realizes Arvid is dead and she cries.
Kristian makes it up the hill and sees some people made it to safety. He calls out to Julia and she runs to him and embraces him. Kristian sees Thomas, and Thomas, seeing Kristian alone realizes his wife didn't make it, causing him to break down.
Back in the bomb shelter, Idun finds an emergency flashlight, and goes over to Phillip to comfort him.
On the hill, Kristian overhears a man talking to some people in cabins over the mountainside. He talks to the person on the line and asks if a tourist bus made it into the area. He finds out that one did not. Kristian fears the worst, thinking his family was on the bus. However, he wants to be sure, and will go down into town to investigate. He tells Julia he needs to find Mom and Sondre and let them know they are okay. He tells her to stay with Thomas and comfort Tessa, telling her she is so brave. Kristian then heads back down the road into town.
In the bomb shelter, Idun finds a fuse box, turning on emergency power. Idun and Sondre try to open the door but the hotel is still fully flooded so only water seeps in. They have no choice but to keep it closed. With other water dripping in, Idun knows they cannot stay in the room forever. Finding a vent, she smashes the grate off then goes up to take a look. The venting is very narrow, most likely too narrow for them to travel through. She screams in frustration. Idun hears metal creak and looks at the door. Water begins to come in through the door cracks so she and Phillip use their coats to slow down the water. Phillip becomes more unstable saying they should take their chances because if they stay in the room, they will die. Idun cautions against hasty moves, noting when the water is above the door, they will try to open it again, hoping the pressure will be much lower.
Kristian rows into town on a boat, with a piece of wood as an oar. He looks around and sees the complete destruction of his town and a dead man floating in the water. After awhile, he must travel by foot, seeing the destruction and death up close. He calls out, hoping to find survivors but hears nothing. He continues to walk until he feels the ground feel unstable. He wipes away mud to find a glass window. He then realizes it is the tour bus. He takes a look inside and begins to check for survivors. He finds the driver, among many others, dead. He checks all the bodies but doesn't find his wife and son. He does however find Vibeke dead. In the end, he realizes no one on the bus survived but his wife and son weren't on it. He sees the destroyed hotel in the distance.
We see outside the bomb shelter door. The entire hallway and above is submerged in water. Inside, the room is almost full. Idun decides to try the door again. The three of them work to unlatch the door, struggling. However, a bunch of rock debris now blocks the door, making it almost impossible to open. They go over to the vent so they can continue to breathe. Phillip begins to panic, dragging Idun and Sondre under the water, yelling he wont die like this. Phillip continues to dunk them both, and in fear for the life of her son, Idun drags Phillip under water and proceeds to lock his head between her legs, trapping him. As she is forced to drown Phillip, Idun tells her son not to look. Phillip drowns moments later.
Kristian gets into the lobby of the hotel and calls out for anyone, getting no response. He checks the hallway and calls out for Idun and Sondre. Part of the roof collapses, scaring him. Kristian finds the basement level, completely flooded and then goes upstairs to check.
Back in the vent, Idun apologizes to Sondre for making him have to see what she did. She tells him to hang on.
Meanwhile, after not finding his family in the hallways, finds Sondre's bag in one of the rooms. He believes his wife and son have been killed and cries. He grabs a metal pipe and begins banging on the wall in anger, sorrow, and frustration. Idun hears the clangs so she and Sondre begin to make noises of their own, hoping someone will hear. Idun goes into the water and finds a wrench and begins clanging on the pipes. Kristian hears this and realizes someone is alive. They begin to make noise back and forth and Kristian races out. However, in the shelter, water begins to fill the vent, giving Idun and Sondre very little time.
Kristian takes several deep breaths and goes underwater. He sees the debris and goes to move it out of the way. Idun goes for the door again and tries to move it as Kristian moves the rocks. Idun opens the door and sees her husband. They embrace, and Kristian communicates her to move to safety while he gets their son. Idun escapes the water and back up the staircase.
Kristian gets into the vent where Sondre is and embraces him. Kristian they have to take one last swim but Sondre is panicking (especially after what happened with Phillip). Kristian calms his son, saying they have no choice, and that he, his mother, and his sister need him. They go under water with Kristian leading first. As they move, Sondre sees Phillips body. As they enter the hallway, the water shifts, and Sondre panics, and begins to drown. Kristian goes back to his son, calms him, and breathes air into his mouth, telling him to go. Sondre continues to swim, reaching the staircase. As Kristian tries to swim too, he has the same problem and runs out of air and begins to drown.
Sondre meets his mother and tells her Kristian is still underwater. She goes back under and grabs her husband and pulls him out. Idun begins CPR and becomes more frantic as it seems to have no effect. After a few minutes she stops, believing her husband is dead. Sondre however refuses to accept it and continues, screaming at his dad to wake up. Finally, Kristian spits up water, and comes to, embracing his family.
Back on the hill, Julia and Tessa play with her bunny, trying to give her comfort. A helicopter arrives, with a survivor. Julia is crushed, thinking her family is gone. As the helicopter leaves though, we see that Kristian, Sondre, and Idun are walking up the hill. Julia happily races up to her mother and who takes Julia in her arms. The family walks toward the group of survivors and emergency res-ponders, grateful to be alive.
Title credits at the end state the Akernes crevice is continuously monitored. It is still expanding by up to 15 centimeters annually. All experts agree there will be a rock slide. However, they do not know when.