Although Richard Burton and Stanley Baker had been close friends since they were teenagers, this was the only time they acted together in a movie. Burton later recorded the narration for Baker's movie Zulu (1964).
Writer/director Robert Rossen was lobbied by photojournalist (and later a co-producer on John Cassavetes films) Sam Shaw to consider John Cassavetes, then a struggling young actor in New York City, for the title role in this movie. Rossen rejected Cassavetes, but the blacklisted director and the young actor became close friends over the course of the next few years. They shared many opinions about dramatic construction, acting and directing, and Rossen would give Cassavetes a lot of help a few years later on Shadows (1958), Cassavetes' directorial debut.