Inner Sanctum (1948)

Starring Charles Russell, Mary Beth Hughes, Dale Belding, Billy House, Fritz Leiber
Directed by Lew Landers
(actor & director credits courtesy IMDB.com)

An elderly doctor on a train tells to a woman a cautionary tale of a murderer on the lam who finds himself stranded in a small town. 

Although purportedly based on the Inner Sanctum novels and radio show, the movie lacks a host or even a creaking door, and is unrelated to the Inner Sanctum films starring Lon Chaney Jr.  It most closely resembles a film noir, with a suspense thriller plot and possessing a cast with no big names.  Made on a low budget independently, it's nevertheless quite watchable, as the murderer (Charles Russell) moves into a boarding house, only to discover the young son (Dale Belding) of one of the tenants witnessed his disposal of the woman he killed.  He tries to find a way to stay undetected but with the bridge out of town flooded, he's caught in a figurative trap.  I wouldn't say there's any standout performances, although most play their parts well, but the film is cleverly written and culminates in a nice twist ending.