Greydon Clark was born on February 7, 1943, in Niles, Michigan, a city located in the state's southwestern region. He attended Valparaiso University, situated near the bustling metropolis of Chicago, where he studied acting under the guidance of renowned coach John Morley. Prior to embarking on a career in the film industry, Clark supported himself by working as a door-to-door salesman.
Clark's cinematic journey began as an actor in several low-budget, yet enjoyable, exploitation features directed by the legendary Grade-Z filmmaker Al Adamson. One of his most memorable performances was as Acid, a wacky and drugged-out biker, in the 1969 film Satan's Sadists. Clark also co-wrote the script under the pseudonym Dennis Wayne. In addition to Satan's Sadists, Clark appeared in Hell's Bloody Devils (1970) and Dracula vs. Frankenstein (1971),both of which were also directed by Adamson.
Throughout the 1970s to the late 1990s, Clark directed a diverse array of pleasingly lowbrow, low-budget drive-in pictures and straight-to-video offerings. His filmography includes the trashy blaxploitation double whammies Tom (1973) and Black Shampoo (1976),the silly Satan's Cheerleaders (1977),the nifty sci-fi/horror item Without Warning (1980),the amusing slasher spoof Wacko (1982),the hilariously raunchy Joysticks (1983),the uproariously awful killer mutant cat camp hoot Uninvited (1993),and the especially atrocious Skinheads (1989).
In addition to directing, Clark often writes and produces his own movies, and sometimes essays small roles in his films. He wrote the script and appeared in a minor part in the fun supernatural revenge opus Psychic Killer (1975). His late actress wife, Jacqulin Cole, also appeared in several of his films.
