Behind Locked Doors

1948, US, directed by Oscar (Budd) Boetticher

A Budd Boetticher from the pre-Budd period. An efficient 60-minute programmer, with an absurd plot (not in the Strange Impersonation sense but rather with respect to the rapidity with which the lead character is able to assemble information: he's a private dick in league with a journalist and goes undercover as a mental patient to uncover a hitherto unassailable secret) and some extremely effective and atmospheric staging. In other words, a pretty perfect example of the genre. It wouldn't take the most skilled of clairvoyants to predict the finale, but several of the shots and the use of light/shadow are striking.