Equus is a 1977 British-American drama film directed by Sidney Lumet and starring Richard Burton. Peter Shaffer wrote the screenplay based on his play Equus. The film also featured Peter Firth, Colin Blakely, Joan Plowright, Eileen Atkins, and Jenny Agutter. Psychiatrist Martin Dysart investigates the savage blinding of six horses with a metal spike in a stable in Hampshire, England. The atrocity was committed by an unassuming 17-year-old stable boy named Alan Strang, the only son of opinionated but inwardly-timid Frank Strang and his genteel, religious wife, Dora. As Dysart exposes the truths behind the boy's demons, he finds himself face-to-face with his own.