Batman has battled some strange villains in his day, but few stranger than Clayface. Bob Kane and Bill Finger, originally envisioned him as a master of disguise who was actually a fallen film actor. Since the Golden Age, the character has gone through several transformations, becoming a regular in the rogue's gallery, and appearing in all forms of media - print, video and film -into the present day. According to Wikipedia:
"The original Clayface, Basil Karlo, appeared in Detective Comics #40. He is an actor who is driven mad when he hears of a remake of the classic horror film he had starred in, "The Terror," even though he is to be one of the advising staff. Donning the mask of the film's villain, Clayface, he embarks on a murder spree among the cast and crew of the remake. He is foiled by Batman and Robin. "
Detective Comics #40 (1940)
Origin of Clayface
reappears in Detective Comics #49 (March 1941) after the prison ambulance he is
riding in plunges off a cliff. He once again dons the mask of Clayface and targets
Bruce Wayne's fiancée, Julie Madison. Once again, the Dynamic Duo foil the evil
Karlo. A movie buff, Batman creator Bob Kane states that the character was partially
inspired by the Lon Chaney, Sr. version of "The Phantom of the Opera"
and that the name of the character comes from Boris Karloff."