When a rich, bored young heiress, Celia, recklessly marries the elusive and mysterious architect Mark, she doesn't realize until after the fact that her new husband's life is filled with strange obsessions and dark secrets. Like many of the films of its day, Fritz Lang's THE SECRET BEYOND THE DOOR evokes Freudian psychoanalytic theory in portraying Mark's bizarre fascination with death. When Celia arrives at her new home, she finds that her husband is so interested in murder that he has recreated a multitude of crime scenes within his own house, one of which he keeps behind a locked door. Seemingly trapped within the spare yet surreal and terrifying confines of the mansion, Celia begins to fear for her life when Mark's real sublimated hatred for women starts to bubble over, and his love of violence leads her to believe that she is next. As this gothic tale veers towards its climax, Fritz Lang--with the help of cinematographer Stanley Cortez--paints a tense and moody portrait of Mark's psyche in crisis offset by Celia's loving devotion, which is the one thing that can save him.