 On an ocean liner crossing from New York to Europe in 1947, a passenger says her name is Mrs. Lindsay Grant, and her new husband Kenneth has disappeared after boarding along with her. What s worse, her key now doesn t fit their double room, but a nearby single room where she finds her luggage, but tagged with her maiden name Thompson. The ship s records show that room booked by Lindsay Thompson, the double room vacant. Lindsay says the maid saw her with Kenneth; the maid says not. Lindsay has no marriage license or ticket; she says Kenneth had them. Radio inquiries reveal that Lindsay had a breakdown after being accused of killing her first husband: could this husband be a figment of her imagination? Only two people, the doctor and a friend Lindsay made during the trip, seem to think she might be telling the truth.