Later, he would just buy foreign films that already existed and re-edit them, dubbing some scenes in English and inserting new footage which he shot with American actors such as John Carradine and Katherine Victor.
[5] Warren is known for producing and directing a number of cult films such as Teenage Zombies, The Incredible Petrified World, Terror of the Bloodhunters, and the aforementioned Man Beast.
[7] Warren released his version in the United States on May 3, 1962[8] as a double feature with his film Terror of the Bloodhunters starring Robert Clarke.
[9] No Time to Kill is a Swedish film, again made in English, starring John Ireland, shot in 1958[12] that Warren purchased, about a man who spends eight years in prison after being falsely convicted of arson.
[14] Added footage on Curse of the Stone Hand, which was released on a double-bill with Face of the Screaming Werewolf, featured John Carradine Warren was hired to film some extra footage in 1965 to pad out the running time of another American producer's film titled Blood of the Man-Devil which starred Lon Chaney Jr. and John Carradine.
[18] Warren produced an all-original film called The Wild World of Batwoman in 1966[19] which stars Katherine Victor and Bruno Ve Sota.
[19] He did not produce another film after that until he released his final motion picture, Frankenstein Island in 1981, starring his biggest name cast of Katherine Victor, John Carradine, Cameron Mitchell, Steve Brodie and Robert Clarke.
[21] Warren's films, specifically Wild World of Batwoman, Invasion of the Animal People and Frankenstein's Island, have been spoofed by the cult television series Mystery Science Theater 3000 and its successful spin-off, RiffTrax.