A female U.S. Federal Marshall investigates a murder while assigned security duty at the science expedition stationed in Antarctica. The film starts with Russians flying a transport plane. The co-pilot tries to shoot all the other men who are passengers. They have a gunfight. Everyone is killed, even the pilot. The plane crashes into the ice.
Kate Beckinsale plays the lead character of Carrie Stetko. She is about to rotate back home for some R&R when a dead body is reported being seen near base camp. She goes with the team leader Dr. John Fury (played by Tom Skerritt) to investigate. They find a dead man frozen in the ice. There is no sign of struggle. An ice hatchet probably made the wound, but the murder weapon is not there. The damage to the body looks as if he has fallen from a significant height. The dead man is from a team, stationed far away from base camp, this is supposed to be searching for meteorite fragments.
Doc suggests they ship the body back in a body bag, so Carrie will not have to give up her time off. There is a storm approaching. It is near the time of year, when there will be darkness 24 hours per day, for a six-month period. No further cargo or passenger transport during that time is possible, so there is only a short window of time available for her to leave. She decides to stay and continue the investigation. This is the first murder on Antarctica in history and the killer may still be amongst them.
On the radio, she gets an urgent call from one of the scientists at the station where the murdered man was supposed to be working. The scientist tells her to come to the station right away so she can see what is going on. She immediately flies out with a pilot named Delfy (played by Columbus Short). When they arrive at the remote substation, they search everywhere. In the last building, Carrie finds the scientist with his throat slit. Suddenly an attack comes from behind, by a man wearing a winter's mask so we cannot see who it is. She escapes his grasp, gets outside, and clips herself to the guide wire to find her way back to the building where Delfy is waiting for her. The wind is blowing hard and the conditions are rapidly deteriorating towards a "whiteout" where it will be impossible to see more than a few inches, when outside, and therefore very easy to get lost in a snowstorm. The murderer is right behind her. She left in such a hurry she did not take her gloves. When she touches the metal door to open it, it freezes to her hand. She loses part of her flesh, which is stuck to the metal door handle, when she pulls her hand away. She barely gets inside, locks the door so the killer cannot enter, and then passes out.
While unconscious, she has nightmares about her time when she was a police officer, and how she survived a vicious attack by a criminal. When she wakes, she sees Delfy and almost attacks him. He calms her and tells her he found her inside the station on the floor unconscious. She tells him there is a killer here with them at this station. After she recovers a bit, they decide to go back to the other building to investigate the second murder. Delfy follows behind her. She enters with her gun drawn to see Robert Pryce (played by Gabriel Macht) examining the body. He shows ID and tells her he is a UN investigator sent there to investigate the murder, now two of them, before there is an international incident. Carrie does not trust him. There is still one scientist from the three-man team unaccounted for, so they think he must be the murderer.
They bring the body back to the main building, where Carrie finds the work log. She figures out where the scientists were last working. They go there in a snowplow vehicle to continue the investigation. When they first arrive, there appears to be nothing important until Carrie falls down a hole in the ice. It leads to the buried Russian plane, that we saw at the beginning of the movie. They find all the dead men in the plane and conclude correctly that it crash-landed.
They notice six canisters are missing from a large metal box that was broken open. While they are investigating, someone else uses another snowplow to bury them by, filling the escape path with tons of ice. Pryce figures out how to get the exploding escape hatch of the plane to work, so they are able to escape.
They get back to the main base. Carrie's hand is in bad condition. Doc performs an amputation of her finger. The missing scientist Rubin (played by Jesse Todd) comes to see Carrie. He says someone is trying to kill him. Carrie tries to get him safely on a plane. The murderer attacks them. Carrie gets the upper hand and knocks the murderer unconscious with a shovel. The killer is Russell Haden (played by Alex O'Loughlin) who works at the main camp. Carrie and Bryce put him in the brig, be he escapes and tries to get to a plane. They chase after him, fight in the snow, which has become a whiteout. Carrie is almost killed. Bryce saves her and kills Russell instead. They bring Russell's bag back inside. They have found the missing containers. Carries wants to open them, by Bryce warns it could be radioactive materials. Carrie hesitates, but says if they were radioactive, they would be marked. She opens one. It contains jellybeans!
Carrie figures out the missing treasure is inside the bodies of the dead scientists, hidden there to smuggle it out. She opens the sutures on one dead body, which look like Doc's work. She finds a large bag of huge uncut diamonds. Doc is there behind her. Doc admits to helping with the plot, but that Russell is the one who got greedy and killed all the others. Doc felt justified in having his part of the treasure because of being stuck so long at this post without adequate compensation and never getting to see his family for years, but he did not want to become a murderer. With that, Doc turns, opens the door to the outside, and walks out into the whiteout of the snow blizzard killing himself.
Best part of story, including ending:
I like tough female cops who have a hard time accepting all the violence in their job, but find a way to deal with it because it makes the story compelling.
Best scene in story:
The best scene is when Carrie finds the diamonds stuffed in the dead body because this is a surprise.
Opinion about the main character:
Running away to Antarctica, to get away from what happened to her, as a cop in Miami, seems extreme. One would think she could pick an assignment in a place not quite as cold.