Carlos Clarens was born in Havana, Cuba. He received his education at Havana University, at Columbia and at the Sorbonne. Clarens started out writing film criticism for a variety of prominent periodicals including Sight and Sound, Cahiers du Cinema, and The Village Voice. He later began assisting such directors as Agnes Varda and Robert Bresson and then worked as a casting agent for Francis Ford Coppola. He has also written English subtitles for foreign films such as Zeffirelli's La Traviata. As an actor, Clarens has appeared in Lion's Love and Flacons D'Or. He has written a definitive film study, Crime Movies (1980), An Illustrated History of the Horror Film (1967) and a study of George Cukor. Clarens also taught courses on crime films in New York and was co-owner of Phototeque, a stills service.