A small science team remains isolated during winter at an Antarctic research station to continue their research in the fight against climate change. With the spring, the entire team are either dead or missing.

A storm builds around the base and the search for Annika must be called off. Pressed by Johan, Maggie tries to remember what happened after Miles' death.

The surviving winterers were now certain that the killer was one of them. The Sno-Cats were their only chance to get close enough to the Argentinian station to call for help.

Arthur reveals that the body found buried in the snow is none other than Sarah Jackson, the scientist who died years ago during the Polaris V accident, a failed mission that ended in tragedy.

The team did not find the radio parts they were looking for. Maggie insisted to take the body found in the Polaris V back to Polaris VI. She claimed it was the right thing to do, but what she really wanted was to do a proper autopsy.

After her confession, Annika insisted on driving the remaining Sno-Cat through the blizzard towards the Canadian base to ask for help. A suicide mission, perhaps, but the right thing to do.