Martin Scorsese was originally hired to direct The Honeymoon Killers. It would have been his first major project but, fatefully, Scorsese was replaced by Leonard Kastle (b.1929). The film was Kastle's first, and last, foray into the world of film directing. He had initially intended the film to be called Dear Martha, but was overruled by producers who wanted a title with greater exploitability. Accompanied by a Gustav Mahler soundtrack, the film is clearly lurid and sensationalist but with a Nouvelle Vague feel. French New Wave director François Truffaut named it his favourite American film and it continues to have a strong following today.

The Honeymoon Killers was based on the true story of Martha Beck and Raymond Fernandez, two infamous serial killers in the 1940s. Dubbed 'The Lonely Heart Killers' by the press, they were eventually caught and executed in Sing Sing prison in San Quentin in 1951.