The film's plot was about a U.S. Senator named Eric Chandler (played by actor Matt Hagen) who suffered an accident that left his face disfigured. A plastic surgeon named Susan (played by medical consultant Stella Bates) eventually manages to heal Chandler's face. Once that Chandler looks at his healed face, his fiancée tells him that they can finally get married as planned previously. However, Chandler does not love his fiancée in reality and discovers that Susan has feelings for him. Finally, Chandler realizes who his true love is and finds Susan crying in the hallway. Both embrace and Chandler confesses to Susan that "she cured more than his body, she cured his heart".
Years after the film's release, by the time Hagen had became Clayface, Bates, now his accomplice, rewatched the film. She cried while seeing it, but Clayface became mad and destroyed the TV where the movie was shown, arguing that the Hagen was not him anymore. Additionally, when Batman decided to investigate about who was Clayface's accomplice, his butler Alfred Pennyworth saw the film to discover Bates' identity.
The Dark Interlude has a plot that is very similar to that of Edmund Goulding's 1939 classic movie Dark Victory, starring Bette Davis. Dark Victory was produced by Warner Bros., and the studio's logo appears as an in-joke at the "The End" title card that shows after The Dark Interlude ends without any end credits, mainly as a reference of how film studios ended their films during the Golden Age of Hollywood.
A poster for the movie would later appear in the video game Batman: Arkham Knight.