Cy Endfield was born in Scranton, Pennsylvania. He attended Yale University and began his career as a theatre director and drama coach, becoming a significant figure in New York’s progressive theatre scene. It was largely the shared interest of magic that led Orson Welles to become aware of Endfield and his recruitment as an apprentice for Mercury Productions (then based at RKO Pictures). One of his independent films was “Inflation” (1940), a 15-minute commission for the Office of War Information that was rejected as being anti-capitalist. The debacle surrounding the production of The Magnificent Ambersons (1942) ended with the expulsion of the Mercury team from the RKO lot and Endfield signed on as a contract director at MGM where he directed a wide variety of shorts (including the last films in the long-running Our Gang series), before freelancing on low-budget productions for Monogram and other independents. He served in the Army in World War II. It was with the film noir The Underworld Story (1950), a United Artists independent production released, that Cy Endfield first came to critical and studio attention. The film was a major leap from anything he had previously produced in regards to budget and social commentary; a coruscating attack on press corruption which could equally be taken as a wider attack on the McCarthyite ideology of the times. He followed this with the film often cited as his masterpiece, The Sound of Fury (aka Try And Get Me!), a lynching thriller based on a true story. Except for the lynch scene, the film was not well received by critics. It was with these two films that Endfield’s signature approach to character developed, pessimistic without being uncompassionate.

In 1951 Cy Endfield was named as a Communist at a HUAC hearing. Subsequently, being blacklisted without work prompted his move to Britain where, under various pseudonyms (to avoid complication with film releases in the U.S.), he wrote and directed films often starring fellow blacklistees, such as Lloyd Bridges and Sam Wanamaker. Three films, The Limping Man (1953), Impulse (1954), and Child in the House (1956) list Charles de la Tour (a documentary filmmaker) as co-director because the ACT (Association of Cine Technicians) insisted Endfield could direct in Britain without being a full member of the union only if he had a British director on set as a standby. Hell Drivers was his first project released under his real name and as well as his debut BAFTA nomination for the BAFTA Award for Best British Screenplay category. Special effects by Ray Harryhausen were a feature in his Mysterious Island (1961). His best remembered film is Zulu (1964). This project was followed by Sands of the Kalahari (1965) with Susannah York. After a few more independent productions he withdrew from film direction in 1971, his final film being Universal Soldier where he made a cameo appearance with Germaine Greer. In 1979 he wrote the non-fiction book Zulu Dawn, which tells the story of the British military campaign against the Zulu Nation in 1879. A film adaptation of the book was released in the same year, co-written by Cy Endfield and directed by Douglas Hickox.

Cy Endfield is co-credited with Chris Rainey for a pocket-sized/miniature computer with a chorded keypad that allows rapid typing without a bulky single-stroke keyboard. It functions like a musical instrument by pressing combinations of keys that he called a “Microwriter” to generate a full alphanumeric character set. It is currently under further development, as “CyKey”, for PC and Palm PDA, by Endfield’s former partner, Chris Rainey and Bellaire Electronics. CyKey is named after Cy Endfield. British magician Michael Vincent credits Endfield as one of his biggest influences. The classic “Cy Endfield’s Entertaining Card Magic”, by Lewis Ganson, includes a variety of Endfield’s creations in card magic. Cy Endfield died in 1995 in Shipston-on-Stour, Warwickshire, England, age 80. He is buried in Highgate Cemetery.