Karate champion Matt Logan is enlisted by the police to train officers in self-defense after narcotics agents are killed by an assailant using the martial arts.
A Force of One is a 1979 American martial arts action-thriller film directed by Paul Aaron and starring Chuck Norris, with Jennifer O'Neill, Ron O'Neal, Clu Gulager, and martial artist Bill Wallace in his film debut. Norris plays karate champion Matt Logan, who is hired to assist an anti-narcotics police unit, who are being targeted by a killer. The screenplay by Ernest Tidyman was based on a story co-written by martial artist Pat E. Johnson.