The boy, John Mohune, is much older in the novel, in his mid-teens at the start; the action of the novel takes place over a period of more than ten years in which he grows to manhood. He spends some of that time in a foreign prison.
Stewart Granger wanted the film to be made in Cornwall. He was dismayed that it did not follow the book.
The character Jeremy Fox did not appear in the novel.
This film was a major flop at the box-office, losing MGM 1.2 million dollars (10.85 million dollars in 2016) according to studio records.
Filmed entirely on the MGM backlot, apart from some scenes of the California coast.