Bear Island is known as the wartime graveyard of the Arctic where Nazi submarines lay in wait for Murmansk convoys. As the charter ship Morning Rose sails toward the island, the doctor on board, Christopher Marlowe, is kept busy tending his sea sick patients - the members of a film unit who are to make a film on Bear Island, a project so secret that none of them know much about it. Then another malady attacks - and in some cases proves fatal. But there is something unnatural about the illness and its selection of victims. There is a murderer on board - and Marlowe knows he's on the elimination list. Someone in the film unit is intent on preventing Marlowe and the others from learning the secret of the island, and what lays beyond the Gates of Pearl.