In 1947 in the New Mexico desert, an operator hears a strange signal on the radio that makes his dog bark like crazy. The man connects a few more machines but can’t understand the weird noise, so he calls another station that tells him the signal is coming from Roswell. Taking the dog and the radio with him, the operator goes for a ride until he sees some smoke and a light in the distance.
His truck suddenly loses power and the dog jumps out barking. The operator follows it and finds the area on fire with something strange in the middle. At that moment he hears a noise and panics as he looks up at a very bright light.
In Antarctica in 2003, a group of scientists sees on the scanner a strange object buried five meters under the ice. Not knowing what to do with it, they decide to send it to a NASA research station. Meanwhile in the University of California, cryptologist Julian is trying to teach his class while a student keeps flirting with him.
Since he’s ignoring her, she emails him a naughty message, but he just closes his laptop. After class Julian meets with Doctor Bachman, who has received a satellite image of the strange object they found in Antarctica. It’s so big that at first they thought it was a fossilized whale, but then they identified a strange radio signal coming from it.
They’ve recorded the signal on a CD that Bachman gives to Julian to study. A few hours later, Julian is obsessed with the hidden meaning of the signal. It has discriminated text and pulse groups, meaning it’s not random at all.
Running a special software on the computer shows the signal has an impressive frequency, stronger than anything on Earth. Julian takes these results to Bachman and convinces him to get him a place in the investigation. In the meantime in a research lab on the Falkland Islands, two scientists also find the strange radio signal and since they can’t figure it out, they send it to an observatory in Arizona.
There, another two scientists notice the signal has been boosted and agree to send it to NASA. A few days later Julian is on a plane reaching Antarctica. A raging storm makes the plane shake like crazy and the pilots are having trouble getting ready for landing since visibility is low.
Thankfully the base has bright lights and the pilots use them as guidance to land. The plane slides for a bit but thankfully comes to a stop before anything happens. When Julian finally enters the base he’s welcomed by Nyla, who shows him around and introduces him to the boss Doctor Gierach.
Next Julian is taken to see the mysterious object, which has been dug out but it’s still covered in ice. Following regulations they’re letting it melt off naturally, although they’ve noticed it’s melting at an unusual rate. Both Gierach and Julian think there’s a chance the object may be extraterrestrial.
Julian takes a closer look and when he touches the ice, a mysterious energy goes up his arm and makes him revisit all the memories from the last few days. When Julian removes his hand, the skin is red. At that moment Julian is found by Doctor Kate, who turns out to be his ex.
She doesn’t believe he can stay out of trouble but still begs him to behave since this project is important to her. That night Julian dreams of something glowing inside the ice. He wakes up in the middle of the night when he hears a strange noise and comes out of his room, noticing a shadow sneaking around and tons of water on the floor.
As he follows the trail, he senses something behind him and turns around, only for the mysterious energy to show him visions of the universe, the New Mexico incident, and strange creatures. At that moment Julian wakes up again, unsure if he dreamed that or not. In the morning Nyla shows Julian their experiment on genetically engineered food, which has allowed them to grow corn in the Antarctica.
The temperature is quite warm in the cornfield so the team works with few clothes on. Julian notices Kate gets along very well with Straub and gets jealous. In the meantime, a government agent and the Secretary of Defense are looking at Julian’s, Gierach’s, and Bachman’s profiles.
It turns out Julian got naughty with a student in the past and that’s why for a few years he left teaching, working for NASA instead. That student happened to be Kate. They also take a look at the signal NASA shared with them and discover it’s identical to the one from 1947.
At the base, Julian spends all his time studying the signal without making much progress. He’s joined by communications officer Grisham, who shares how he found the signal coming from the ice. For lunch, the duo goes to the mess hall and Julian gets to meet the rest of the crew.
They ask him about his job and Straub mocks him for believing in aliens. Sometime later, the crew discovers they’re having a communication blackout, which happens often if there’s a storm. Julian checks on the object and is amazed by how much the snow has melted, pointing out they can almost see the object itself now.
Nyla thinks she can feel a low-grade impulse in her joints but when she tries to touch the ice, Julian warns her not to do it. The signal hadn’t been harmonic when Grisham first found it, which means now there are two or more separate frequencies combined in one signal. Since Julian can’t connect to the satellite, he convinces Grisham to get him an antenna and connects his computer to it so he can continue analyzing the signal.
The next morning the whole building shakes for a few minutes and the mysterious object falls from its hangers. The crew goes to check on it and finally sees the object itself because there’s little ice left. It looks like nothing they’ve ever seen before and when Kate touches it, she is hit by an electric shock.
They conclude the object is igneous rock formed by an eruption, which points toward a meteorite. The signal is exactly like aircraft retrieval data, so Julian believes it’s a black box. As he rushes back to his computer, he explains his theory: this object fell on Earth by mistake and it’s sending a signal to be rescued.
Using all this new information combined with math, Julian finally manages to decipher part of the message. They still can’t understand it and Straub mocks him for it. The group takes a snack break and Straub insists the idea of aliens it’s crazy, but everyone else agrees with Julian’s theory.
At that moment they’re called back to the maintenance bay because a crew member has found a crease on the object. The team discusses the idea of opening it and Kate worries about potential virus or other pathogenic organisms, but Straub points out the labs are sealed environments and they all agree to open it in the morning. Meanwhile Bachman is called to the White House to discuss some terrible news regarding the mysterious object.
Contacting the base is still impossible because of the weather but the government has already allied with a Russian submarine in and sent it toward the base with nuclear warheads ready to launch. The next morning the team connects the object to one of their machines using cables and provokes an electrical reaction that neutralizes the shocks. The object is still generating current inside, but now they can touch it without getting hurt.
Then they use a saw to start cutting the object open, finding a softer layer under the tough outside. Gierach takes a piece from the object and confirms it’s some carbon alloy that was exposed to extreme heat. On Julian’s computer, the message keeps changing and he tells Nyla the object is trying to communicate.
When Nyla says it’s like the videogame MindMaze, it gives him an idea on how to tackle the message and after some trial and error he finally manages to translate it: it says “do not open”. Julian and Nyla freak out and run to the maintenance bay, but when they get there it’s too late. A glowing energy is coming out of the object and making the saw man scream in pain.
His body starts melting and soon an explosion happens, hurting multiple crew members and destroying most objects in the room. It also brings down the generator, which shuts power down in the base until the emergency batteries take over. After getting some flashlights, the rest of the group goes down to the bay to check on the wounded employees.
Everyone is alive except for the sawing guy, who has burned to death. When they take a closer look at the hole the saw left in the object, they’re surprised to discover weirdly-looking organic parts. Pilot Tony pokes it with a broom handle and the membrane starts burning away until a new hole reveals what’s truly inside the object: a frozen alien.
They can’t tell if it’s just sleeping or actually dead. Suddenly Nyla says she feels sick as her nose starts bleeding. She falls on her knees and her face begins melting as well.
Soon more and more employees start going through the same, making the group realize there’s some kind of virus that escaped from the object and is now in the air, killing them one by one. Horrified, the few survivors run into a sealed room to be safe and watch the alien on the security cameras. Grisham tries to contact someone for help but the comms are still down.
Gierach explains a disease sometimes slows down to avoid killing the thing it needs to live on, so there’s a chance the survivors may be infected as well. While the group fights over what to do, the alien opens its eyes. By the time the crew looks at the screen again, the creature is gone from the bay.
They agree to go looking for it and to get the guns brought by the pilots. Using just their flashlights, the crew starts searching the maintenance bay. Straube gets scared when he feels something at his back, but it’s just Kate.
Grisham is also searching, unaware something is watching him from afar. It goes away when Grisham turns around with his flashlight. The presence then starts following Tony, who screams when he sees something moving in the shadows.
As Julian tries to climb over some boxes to reach the next base level, Kate turns off the power in the rooms they aren’t using and Julian falls. He recovers quickly and begins following a weird noise until he finally finds the alien, who appears to be scared. Julian puts down his flashlight while using gentle words, trying to prove he’s friendly.
The alien slowly comes out and puts its claws near the flashlight, absorbing its energy until it’s off. Then the alien approaches Julian and carefully grabs his head with both hands, sharing the energy. When the alien opens its eyes, Julian begins having beautiful visions of the rest of the universe.
At that moment the others show up and Traub tells Tony to fire his gun. The bullet hits the alien and from the resulting wound, a strong energy beam comes out, knocking down Tony and Grishman when they try to come closer. Once all the energy has been expelled, the alien falls and dies, causing its body to disintegrate to the point of disappearing.
Tony explains he thought the alien wanted to kill Julian, but he disagrees saying the alien’s touch felt safe. It didn’t change into fear until Tony showed up. At that moment the White House finally finds a hole in the storm and gets in contact with the base.
Bachman explains they know about the alien and the infection, so Julian assures him this illness hasn’t left the base. Then Bachman also tells them about the New Mexico incident and the killing pathogen, which the aliens are immune to. These creatures communicate with each other through telepathy and have already killed everything on Mars.
When Julian announces the alien is dead, the Secretary of Defense decides blowing up the base is the only option they have to get rid of the virus. He wants Bachman to lie to the crew and tell them help is coming, but Bachman refuses and only tells them “a Russian submarine is on its way”. Julian reads between lines and asks how many hours they have, to which Bachman responds three.
After the conversation ends, Straub freaks out and says he wants to leave on the plane even if the storm is bad. Julian reminds him they’re infected and leaving means taking the virus to the outside world, but Straub thinks that if they were actually infected they’d already be dead. As the submarine comes closer, the scientists run some blood tests to confirm they aren’t infected, although Julian points out this new virus could be insignificantly tiny and hiding in the protein.
Straub sees this as a signal to leave and Tony supports him, but the others don’t. Kate’s lack of support makes Straub mad and he insults her as he tries to attack her, but Julian moves faster and knocks him down with a punch. Suspecting that Straub and Tony will try to leave anyway, the others take Tony’s gun and go around changing the passwords on the locks.
In the Russian submarine, they get ready to shoot the nukes in eighteen minutes. At the base Kate and Julian finish changing the last lock and hold hands to comfort each other until they hear a shot. In the mess hall, Straub and Tony have jumped on Grisham together and use a fork to stab him in the neck.
In the struggle, the gun is shot multiple times and the bullets hit the wall, the ceiling, and Gierach’s shoulder. Once Grisham passes out, Straub and Tony grab the gun and start running at the same time Julian and Kate come back. Straub shoots again, hitting Kate in the shoulder too.
Gierach realizes the two men will be escaping through the drainpipes in the cornfield and sends Julian after them. By shooting all the locked doors down, Straub and Tony make it to the cornfield. As they run, their mere presence begins killing all the corn, confirming they’re indeed infected.
Tony changes his mind and wants to stay, but Straub still wants to escape and threatens Tony with the gun. At that moment Julian appears at the window and Straub shoots at him first, but Julian ducks just in time. Tony uses the distraction to jump on Straub and starts fighting him for the gun.
After some struggle, Straub overpowers him and shoots him down. Hearing Julian approaching, Straub continues to run away, killing every plant in the room as he passes by. He tries shooting Julian a couple of times but always fails.
Eventually both men get into the pipes and quickly cross them to then find a huge set of stairs. The chase continues as they go up and Straub keeps on shooting to no avail. When he finally reaches a hatch, he immediately rushes outside only to find a vortex of energy that traps him.
Julian comes out too yet an invisible barrier keeps him from moving further. He tries telling Straub not to move and to breathe slowly, but Straub doesn’t listen and continues to panic because he can’t breathe. Little by little the energy covers Straub’s body and disintegrates him until there’s nothing left.
The energy slowly covers Julian as well, only to show him more places in the universe and the incoming nuke. Julian finally understands the energy vortex is an alien spaceship that came to rescue the now dead alien and he runs back inside to get the remaining survivors: Kate, Gierach, and a scientist girl. He opens the front door to go outside faster and others are a bit wary at first, but they quickly understand when they see two aliens inside the vortex.
The girl and Gierach go ahead first, then Kate and Julian follow them while holding hands. The spaceship absorbs all four of them and flies off right before the nuke hits the base, blowing it up. A few hours later, the government sends out a cover-up story saying the base was destroyed by an experimental nuclear reactor and calls all the dead people fallen heroes.
However the four survivors are now flying through space.