In this suspenseful drama, based on a John Dickson Carr novel, blissfully happy newlywed Ruth Bowman (Jeanne Crain) boards a transatlantic ocean liner with her new husband John (Carl Betz). A few days later, however, John suddenly disappears. Ruth quickly discovers that her cruise ticket was made out under her maiden name, and that her "husband" never even bought one. To make matters worse, no one on board admits to ever having seen them together. Only the ship's doctor (Michael Rennie) believes the distraught bride's story. Together they discover the truth about her husband's disappearance.