A man calling himself Henry Faber (Donald Sutherland) is actually "the Needle," a German spy in England during World War II. The Needle dropped out of sight in Germany in 1938 and now inhabits a series of drab bed-sitting-rooms in England while he spies on the British war effort. He is known as the Needle because of his trademarked way of killing people by jabbing a stiletto into their rib cages. He kills with a singular lack of passion, and will kill even the most innocent of bystanders if he thinks they might somehow threaten his objective, or just get in the way.The Needle is a very lonely man. He was raised by parents who did not love him, he was shipped off to boarding schools, and he spent parts of his childhood in America, where he learned English. Perhaps none of these experiences fully explains his isolation and ruthlessness, but maybe it's just part of being a spy. The Needle manages to remain in Britain until the eve of D-Day in 1944, when he learns that the D-Day invasion is to take place on Normandy, and he discovers phony plywood "airplanes" intended to look, from the air, like Patton's invasion force, but it's a ruse to throw off the Germans. Hitler has summoned Faber to come brief him about the Allied invasion plans in person. In his attempt to return to Germany with the information, the Needle travels by boat to an area off the coast of Scotland, intending to rendezvous with a German U-boat, but a fierce storm strands him on the nearby Storm Island.Storm Island is isolated and occupied only by a lighthouse-keeper and by a young married couple, a woman (Kate Nelligan), her partially paralyzed husband David (Christopher Cazenove), their son, and their shepherd, Tom.Lucy is frustrated, mired in a loveless marriage with her emotionally damaged husband. David had been a Royal Air Force commander, but he was paralyzed as a result of an automobile accident on their wedding day.The Needle pretends to be merely a lost sailor. And Lucy, frustrated by her husband's drunkenness and refusal to love, becomes attracted to him. They make love. She grows fond of him. It's not clear if he's fond of her, but he tells her things he has told to no one else. The love affair suggests there's a sympathetic personality buried somewhere inside the Nazi spy, though he remains enigmatic. Early on, we discover that he may not enjoy the hand life has dealt him. When a courier asks him about the way he lives, and "What else can one do?" the Needle answers, "One can just stop."The Needle kills David and the lighthouse-keeper. Lucy realizes that her lover has been lying to her after she discovers David's body, and she prepares to turn him in. The Needle must get to the only radio on the island in time to report to his superiors the exact location of the D-Day invasion. Lucy is the Allies' last chance to keep the details secret. Tension mounts as the Needle races against time to make contact with the U-boat and/or stop Nelligan before she blows the whistle on him.The Needle threatens Lucy, first in a psychological way and then with violence. "The war has come down to the two of us," Sutherland tells Nelligan, as they struggle with what they should do. Nelligan isn't sure if Faber is a treacherous spy or an unloved child, but in the end, she shoots him as he tries to escape in a boat.