Directed by William McGann, Sh! The Octopus follows detectives Kelly (Hugh Herbert) and Dempsey (Allen Jenkins) who are in pursuit of a mysterious master criminal known as The Octopus.
The detectives find themselves inside a haunted lighthouse full of suspicious characters, including the titular character, who appears to be an actual octopus.
The film became known for its one take transformation scene that was carried out in a similar manner to 1931’s Dr. Jekyll and Mr. Hyde. The actress involved in the scene was made up with exaggerated highlights and shadows (including her teeth) using a single colour shade of makeup. This make up was invisible on camera due to a special filter. As the filter was removed and specific lighting changes were made, McGann was able to pull off a shocking transformation (now known as the Karl Struss technique after the man who came up with it) that is only possible on black-and-white film: