Hoping to prove to her insurance-investigator uncle that she's a good detective in her own right, Jane Martin (Claire Trevor) pretends to be a jewel thief so that she can infiltrate a criminal gang. She quickly ingratiates herself with suave but deadly crook Frank Peyton (Cesar Romero), and before long Jane herself is in charge of the gang! Once Peyton begins to suspect that Jane has ulterior motives, he does his best to trip her up, even committing a murder in her presence, but she manages to keep up her facade long enough to enable detective Walsh (Lloyd Nolan) to round up the criminals. Despite the cold-blooded nature of his character, Frank Peyton emerges as the most appealing character in the picture; also, while Peyton enjoys a brief onscreen romance with the heroine, nothing of a similar nature develops between Jane and nominal hero Walsh. In short, 15 Maiden Lane is not your average "B"-grade crime meller.
by Hal Erickson synopsis