A woman's happiness is threatened when she discovers her husband has been suffering from amnesia.

On 11 Nov 1918, "Smith," an amnesiac, shell-shocked officer, who has lived in a county asylum in Melbridge, England for many months, wanders into town for the first time, attracted by the sounds of celebration at the end of World War I. In a tobacconist's shop, Smith's hesitating speech alerts the owner that he is from the asylum, but a kindly entertainer, known as Paula Ridgeway, whispers that he should leave, then takes him to a local pub. Paula invites him to her show and gently draws him out. Because "Smithy," as Paula calls him, has come down with the influenza, she and her friend, barkeep "Biffer," take him in and nurse him back to health. Smithy thrives under Paula's care and she obtains a job for him with her troupe. When an asylum caretaker reveals that they are still looking for a missing inmate, though, Paula runs away with Smithy and takes him to a small town in Devon. They stay at a local inn, and soon she gets a job as a typist, while a thriving Smithy begins to write. When he sells his first article to the Liverpool Mercury , Smithy tells Paula that he loves her and proposes. After their marriage they move into a small cottage, and in November 1920, Paula gives birth to a baby boy. A few days later, Smithy receives a telegram from the Mercury asking him to come to Liverpoool to discuss a permanent position on the paper. Because Paula is still recovering from a difficult birth, he reluctantly travels alone, planning to return the following night. After checking into his hotel, Smithy walks toward the Mercury office but is hit by a car and knocked unconscious. When he comes to, he has no memory of the past three years and recalls only his life as aristocrat Charles Rainier. Although confused, Charles returns home, where he finds that his father has died and his siblings are anticipating their inheritance. He also meets Kitty, the teenaged daughter of his sister's new husband. By 1932, Charles has become known as "the industrial prince of England" for vastly increasing his family's fortunes, but is haunted by the missing past that is tied to a latchkey he found in his vest pocket after the accident. He has been loyally served for two years by his private secretary, Margaret Hanson, whom Charles does not recognize as Paula. One day, while dining with Kitty in a London restaurant, Charles hears the voice of Melbridge psychiatrist Dr. Jonathan Benet and is briefly reminded of something in his past, but, as always, the memory passes before he can capture it. That same day, Charles tells Kitty, who has always loved him, that he returns her feelings and later announces to Margaret that he is going to marry Kitty. Margaret, whose son died in infancy, struggles to maintain her composure and that night begs Benet, who has become a good friend, to let her tell Charles everything. Benet makes her realize that Charles has to find memories of "Smithy" on his own. On the day that Kitty and Charles are selecting music for their wedding, one melody inexplicably reminds him of his past and he momentarily looks at Kitty as if she were a stranger. Seeing her cry brings him back to the present, but she tells him that they cannot go through with the wedding because he can never return feelings for her that belong to someone from his past. After Charles goes to Liverpool for clues to his past, Margaret follows him to say that the Liberal party has requested that he stand for election to a newly vacated seat in Parliament. While in Liverpool, Margaret tries gently to lead him to clues about his lost life, but even finding "Smithy's" suitcase does not jar his memory. Charles is soon elected to Parliament and confesses to Margaret that from time to time he has had the feeling that he knew her in the past. He then proposes that they marry in a kind of "merger" in which she would help him in his political life and says that he can offer only sincere friendship. She discusses the proposal with Benet, who loves Magaret himself, and disregards his admonition that she will be hurt. After Margaret and Charles marry, she becomes his greatest asset and dearest friend. Charles is soon knighted and on their third anniversary Charles gives her an expensive necklace. Despite Charles' affection and friendship, Margaret yearns for the love she shared with Smithy and decides that she needs to go away for a few weeks. As Charles uneasily sees her off on the train, he receives word that there is labor unrest in his cableworks in Melbridge. He soon settles the dispute, and as he goes through the town, he surprises his assistant, Harrison, by going right to the tobacconist's shop, even though he had just said that he had never been in Melbridge before. The next day, Margaret, who had been staying at the old Devon inn, learns from the proprietress that a man has just been by asking for the former owner and inquiring about a nearby cottage. Margaret then rushes to her old home. At the cottage, Charles's memories begin to flood back as his latchkey opens the front door. When Margaret arrives and calls him "Smithy," he finally recognizes that Margaret is Paula and the two happily embrace.