I’ve been slacking in my film noir reviews. I’d apologize, but I can’t imagine any of you actually care.

The first fifteen minutes or so of The Dark Mirror are terrific. A man is stabbed to death in his apartment. Several witnesses put the man’s girlfriend Terry Collins (Olivia De Havilland) at the scene. But when Lt. Stevenson (Thomas Mitchell) questions her, she provides several witnesses that can prove she was nowhere near the murdered man at the time of his death.

What the…? How can that be? Twins, that’s how. Terry has an identical twin sister named Ruth (also De Havilland). So, one of them did kill the man but the other has an airtight alibi. Trouble is no one can tell which one did what except the two sisters, and they aren’t saying.

The film has a lot of fun playing with that situation, befuddling the lieutenant at every turn. But then it introduces a psychologist, Dr. Scott (Lew Ayres) who has made a career out of studying twins. He begins seeing the girls individually, running them through a series of tests. Naturally, he also falls in love with one of them.

One of the twins is insane and has been gaslighting the other their entire lives. Naturally, there is a bit of a switcheroo with the twins, because you can’t have a movie about twins without having them pretend to be each other at some point. Once the doctor is introduced I started losing interest. He all but pushes the lieutenant out of the way and the story becomes less about a cop trying to solve a murder and more about a doctor analyzing patients. Boring is the word.

De Haviland is great. She creates two distinct characters out of the sisters while still making them fully believable as twins. Michell is very enjoyable as the lieutenant as well. I wish the film had stuck with him instead of getting all psychobabble with the doctor.