 Terence and Sandra Marsh acquired the screen rights to Dennis' book, which was going to be their first major feature for their new company, Soundcross Film Ltd.They were offered the chance to develop the property at Warner Bros. Terence Marsh received a writing credit for collaborating on the adaptation with Ronny Graham.Terence Marsh wanted to make his directorial debut on the film, but understood that the project would have a better chance with an experienced director and instead hired Richard Lester to direct.