Dementia 13 (released in the United Kingdom as The Haunted and the Hunted) is a 1963 horror thriller film written and directed by Francis Ford Coppola in his feature film directorial debut, and starring William Campbell, Luana Anders, Bart Patton, Mary Mitchell, Eithne Dunne, and Patrick Magee. The film was produced by Roger Corman for his company The Filmgroup, and released in the United States by American International Pictures during the fall of 1963, as the bottom half of a double feature with Corman's X: The Man with the X-ray Eyes.

Although Coppola had been involved in at least two sexploitation films previously, Dementia 13 served as his first mainstream "legitimate" directorial effort. Corman offered Coppola the chance to direct a low-budget horror film in Ireland using funds left over from Corman's recently completed The Young Racers, on which Coppola had worked as a sound technician. The producer wanted a cheap Psycho copy, complete with gothic atmosphere and brutal killings, and Coppola quickly wrote a screenplay with Corman's requirements. Although given total directorial freedom during production, Coppola found himself at odds with Corman after completion. The producer declared it unreleasable and demanded several changes, including added scenes by directors Jack Hill and Monte Hellman.

In 2017, Coppola's company, American Zoetrope, restored the director's cut under the supervision of James T. Mockoski, with editing by Robert Schafer, sound restoration by Jim McKee of Earwax Productions, and color supervision by Chris Martin of Mission Film and Design. The film is in the public domain.