In 1942, the [I]S.S. Queen of Glasgow is one day out of Liverpool, heading for New York. It is traveling through the fog after losing its convoy. On the deck, a passenger named Lanser looks out into the night. The first officer calls out to the crew to black out the lights in the salon. The steward comes out and informs Lanser that he should go in if he wants to eat.
Lanser enters the dining room and notices that a young girl has dropped her doll. He picks it up for her and one of the passengers, Jerry Potter, comes over and introduces himself. Potter explains that they looked for him at dinner because they were wondering where he was. He invites Lanser over for coffee and the man reluctantly sits down. Potter introduces their fellow passengers, Major Devereaux and his secretary, Miss Stanley. They ask if he's heading toward or away from home and he hesitantly says that he's heading away.
Captain Wilbur comes in to greet them and explains that he took his supper on the bridge. Devereaux asks about the convoy and Wilbur says that the fog is too thick to spot them. He hopes to make contact in the morning and Devereaux worries about the German wolf packs converging on them. Lanser abruptly says that the Germans don't converge on a single ship as a matter of principle. Wilbur admits that Lanser is correct and notes that their danger would lie in a single sub. When Potter complains about how a sub would sink them with a torpedo Lanser describes with some authority how the submarine would surface and shell them with impunity. Wilbur comments that Lanser sounds like a U-boat commander and the passenger nervously drops his coffee.
Wilbur makes small talk, apologizing for how the ship wasn't equipped for passengers. He asks Lanser where he comes from and the passenger uncertainly says that he was born in Frankfurt, Germany. Lanser can't remember how long he was in England and then claims illness and goes to his cabin.
The ship continues through the fog and Miss Stanley is going to her cabin when Lanser approaches her. He asks if they've met before and she assures him that she hasn't. Lanser says that she looks familiar as do the rest of the passengers. He talks about how everything feels like he has done it before. Miss Stanley sympathizes, saying she's had the same feeling, but Lanser says that he doesn't remember getting on the ship. He tells Miss Stanley that the first thing he remembers is standing on the deck hearing them in the mess hall. Lanser knows who he is and starts to say that he was in something... but then can't remember what. Miss Stanley suggests that he get some sleep, but Lanser says that he feels like he's in a waking nightmare with disaster coming. He blurts out that there is a U-boat out there, stalking the ship. The First Officer comes over and asks Lanser to meet with the captain.
On the bridge, Wilbur asks Lanser for his passport. On the manifest, Lanser's passport number wasn't put down. Lanser says that it's in his cabin and the First Officer says that he can get it anytime. Wilbur asks if there is anything that he wants to tell them and Lanser insists that he only remembers a few things. He knows his name and where he was born, but that is all that he knows. Wilbur points out that he has a working knowledge of U-boats but it doesn't help him remember. The captain tells Lanser to go to bed and they'll talk more in the morning. Once he goes, Wilbur tells the First Officer to send a steward to Lanser's cabin to get his passport.
As Lanser goes through his luggage, the steward notices a German naval captain's cap among his belongings. Lanser snatches it away and says he'll put it back himself, and notices his nametag inside.
As the Glasgow
continues on, Wilbur calls on the engineer, McCloud, to give them full speed for a few hours. He says that he'll do what he can and Wilbur warns the First Officer that if they don't catch up to the convoy then the German will eventually find them.
Lanser goes to the bar to drink and the bartender points out that it's late. The passenger says that the engines sound labored and notes that it's 12:05 a.m. Lanser says that something will happen at 1:15 but he doesn't know what except that the time sticks in his mind. The First Officer comes in to get a tray for the bridge as the engines stop. Lanser asks the officer why and he says that it's routine maintenance. The passenger disagrees, saying that they're adrift and defenseless. When the First Officer says that they'll soon be repaired, Lanser says that they'll drift until 1:15.
The time passes until 1:15 and Lanser says that they must abandon ship. He looks around and discovers that the bartender has vanished. As he goes out on deck, a spotlight pins him and Lanser realizes that it's the U-boat. He runs from cabin to cabin, yelling for everyone to leave. All of the cabins are empty and no one answers him. Lanser finally finds the passengers, all gathered together and staring silently at him. As he screams at them, they disappear and Lanser runs back up to the deck, calling for the passengers and the crew. Lanser grabs a pair of binoculars and looks at the U-boat... and sees himself, standing on the deck.
The sub crew ready the deck gun and the sub commander orders them to open fire on the Glasgow
. The passengers and crew reappear, dying as the U-boat crew opens fire with the machineguns. Lanser falls overboard and lands in the ocean waters as the ship goes down.
The German U-boat submerges and Captain Lanser goes to his cabin. Lt. Mueller comes in and Lanser says that they had a good catch. The captain realizes that he's shaken and demands an answer, and Mueller admits that he finds it difficult to reconcile killing innocent men and women without warning. He wonders if they may be damned in the eyes of God but Lanser dismisses him as a fool and a mystic. Mueller persists, wondering if that if they are damned, they may be doomed to a hell where they suffer the agony of their victims, dying every night for all eternity.
Soon Lanser finds himself aboard the Glasgow
yet again, riding the ghost of the ship every night for all eternity.