Coast Guard officers Sanna Tanner and Joonas Kapanen are trapped on an icebreaker during a rescue operation. The crew seems paranoid and secretive. When the chief engineer attacks Joonas, Sanna rushes to his aid, with deadly consequences.

The night turns eerie and dark. One crew member accidentally shoots another, while two others disappear. A disturbing and malicious presence seems to be affecting everyone. The crew plans an escape on the hovercraft, but disaster strikes.