In the early 1960s, an English publisher, Gordon Landsborough, attempted to produce a film version of the book and wrote a film treatment for it. When he discovered that MGM still held the film rights he attempted to buy them but was unsuccessful as MGM announced their interest in filming it, using a script by Carl Foreman. Landsborough wrote in 1965 of rumours of political pressure holding up that new MGM production. Another movie version was mentioned in the 1967 sales film "Lionpower from MGM", as being slated for production in 1968–1969 but nothing came of this version either.