Somewhere in the Night starts with the hero, played by John Hodiak, in an Army field hospital, encased in bandages, unable to even speak. But his internal dialog lets us know that he has lost his memory. He only learns his name when someone mentions it. Little do we know, but we have seen this movie before, and like the hero, forgotten it.
Hodiak discovers he has two links to the past: an unsigned letter from his ex-fiancee, telling him what a heel his is, and a letter telling him there was several thousand dollars in a bank account for him, signed by Larry Cravat. That was when we remembered we'd seen the movie before. You don't forget a name like Larry Cravat.
So Hodiak tries to find out who he is, but not too hard, because he is afraid that he is a rat. Trying to track down Cravat, he runs into Harry Morgan in a gym and Nancy Guild and her boss Richard Conte in a nightclub. Nancy Guild is a funny kind of nightclub singer - she seems to be singing on break from studying English or history at Wellesley. Conte is clearly stuck on her, but he's too straight to make a play or try to break up her romance with Hodiak Funny kind of noir nightclub owner.
Later, he runs into bad girl Margo Woode, who evidently knows what kind of movie she's in, because she frequently namechecks films noir like Double Indemnity. When someone feeds her a snappy line, she responds, "Oh, so we're doing repartee?". Touches of self-consciousness like this really make the movie for me.
I'm not sure I can say this is great noir. It's directed by Joseph L. Mankiewicz, better known as a writer and producer. It's a touch indulgent, a little ripe at the core, and the mystery doesn't make as much sense as you might expect. On the plus side, it's a great example of the post-war amnesia genre, and it's 110 minutes long. That's a lot of noir for the money.