When businessman Philip “Vic” Vickers returns unexpectedly to his English mansion after a four year absence, he startles Joan Merrill, his wife’s social secretary, as he had been presumed dead. Joan tells him that his wife Angie is attending a party in the large cottage by the river on the mansion grounds. When Vic asks a party guest where his wife might be, he is told that she is probably with one of his business partners, Job Crandall, Bill Saul or Harry Bryce. In the kitchen, Vic surprises Job, who drops a glass in astonishment at seeing Vic alive. Bill is equally alarmed by Vic’s return. Vic spots Angie in the distance, leaving on a motor launch. In the morning, over breakfast, Job and Bill ask Vic where he has been for four years, but he does not respond. Soon after, the motor launch returns to its mooring and Angie walks into the kitchen and faints when she sees Vic. Vic carries her to a bedroom and, when she recovers, she embraces him saying that she knew he would come back. Angie tells Vic that four years earlier, she received a telegram from Job in Portugal, where he, Bill, Harry and Vic were on a fishing trip, stating that Vic had disappeared. Vic tells Angie that he has had amnesia and can only remember being in a small Portuguese harbor when he was drugged, knocked out and left for dead by one of his business colleagues. Vic woke up on a Mexican ship with no identification or memory. Vic tells Angie that he suspects one of his three friends attempted to kill him and wonders if she, too, might have been involved in the plot. Bill interrupts them with the news that Harry has been found dead at the mooring. Police inspector Treherne establishes that Harry was killed from a blow to the head by a steel pipe and states that he regards all at the cottage as suspects. Later, Vic sends Joan and the servants away as he wants to spend time alone with Angie and hopes to force the killer to show his hand. Joan tells Treherne that she is concerned about Angie because she suspects Vic of killing Harry, who was in love with Angie. Treherne then reminds Joan that she has a motive for incriminating Vic as Vic’s company bankrupted her father, causing his suicide. After a bloody handkerchief, with the initial “V” on it, is found near the murder scene, Treherne is about to arrest Vic when Angie saves him by saying that she had given the handkerchief to Harry. After Treherne leaves, Angie tells Vic that her statement was true. Meanwhile, Sessions, the company accountant, is trying to blackmail Job, who has been embezzling from the company. During an argument, Job accidentally kills Sessions. Job, who suspects that Angie was responsible for Harry's death, offers to save her from arrest by confessing to that crime as well. When Bill visits the mansion, he tries to persuade Vic that the attempt on his life was not perpetrated by any of his companions, although they all resented him, and that he has created this fantasy in his mind. Later, Treherne feels that he may have enough evidence to arrest Angie for Harry’s death. In order to save Angie, Joan concocts an account of how she was involved in the death, but is not believed. Although Vic now believes that Bill may have been the one who tried to kill him, he and Angie invite him to dinner. After the meal, Bill mixes them all nightcaps. Some time later, a drugged Vic wakes up with a poker in his hand and Joan’s dead body nearby. Vic then drives to Bill’s house where Bill shoots him in the hand. Vic knows that Bill, like the others, has been pursuing Angie romantically and tells him that he has killed her. When Bill attempts to phone to confirm this, Vic disarms and overpowers him. Bill eventually confesses that he attempted to kill Vic and killed Harry because he was paying too much attention to Angie. Bill also admits killing Joan in order to cast suspicion on Vic. Treherne and his officers, alerted by Angie, arrive and arrest Bill. Vic and Angie return to their home to resume their lives.