Prisoner of Ice begins during the run-up to
World War II, primarily around Antarctica. The main character is a young U.S. intelligence officer, Lt. Ryan, who has been assigned to a British submarine, HMS
Victoria, for a special mission. As the game begins, the submarine is fleeing the Antarctic after rescuing a Norwegian who has recently escaped from a secret German base in the Antarctic (it is later revealed that the base is built atop the Ancient Ruins mentioned in
At the Mountains of Madness). Along with the Norwegian, the sub has picked up two mysterious cargo crates stolen from the Nazis. Late in the game, in Argentina, Ryan meets John Parker, the central character from
Shadow of the Comet, and reveals the links between the two games. Narackamous, the main antagonist of
Shadow of the Comet, also returns. The game has a choice of two endings, though there is little difference between them. ==Gameplay==