Robert Lippert had been impressed by Jack Nicholson's
Thunder Island so gave Nicholson and his friends Monte Hellman and John Hackett $160,000 and $400 a week salary to make two films on location in the Philippines. The three men and Hellman's wife and child traveled 28 days by ship via Hawaii, Hong Kong and Japan with the three working on the screenplays to both films on the voyage.
Back Door to Hell was a rewrite on one of Lippert's existing screenplays. Popular singer
Jimmie Rodgers had a substantial part in the film, and co-financed it. The film, directed by
Monte Hellman, was shot on location in
Vinzons,
Camarines Norte,
Philippines, giving it an authentic look. The same plot was reused in
Ib Melchior's
Ambush Bay (1966) with a larger Marine patrol destroying a
minefield prior to the American and Filipino invasion of the Philippines. ==Notes==