Take One False Step (1949)

Take One False Step (1949) is an innocent-man-accused murder mystery comedy-toned film noir by Chester Erskine, which follows decent upstanding citizen Andrew Gentling (played by William Powell) as he negotiates the criminal backdrops of San Francisco, trying to clear his name from the frame, and deal with a rabid dog bite in the process.

In town for a conference, Powell's character bumps into an old flame in the form of Shelley Winters, and she relentlessly hits on him until he drives her home, and she disappears, leaving him suspected of murder.

It's a murder without a body however, and an ordinarily tense noir setup falls into place and the hacks of film noir will argue that it winds up lacking in the tension that is traded for comedy.

Crossroads (1942)

Crossroads (1942) is an amnesia mystery film noir starring William Powell, Hedy Lamarr, Claire Trevor and Basil Rathbone, and directed by Jack Conway. 

William Powell plays a diplomat whose amnesia about his past subjects him to back-to-back blackmail schemes, which threaten his reputation, job, marriage, and future. 

The film was based on the 1938 French film Crossroads which had also had a British remake called Dead Man's Shoes in 1940.

With shimmering cobblestones and foggy streetlamps, and deception, blackmail and a surprising if dubious mystery story, Crossroads (1942) is a prime example of 1940s amnesia noir.