Sara Montiel was originally cast in the role of Teresa and filmed some sequences in Brazil's Matto Grosso jungle. There are stills where she is seen handling a big snake, possibly an anaconda, along with Glenn Ford, Cesar Romero and others in the cast. In her 2000 autobiography, Sara relates how the production ran out of money and everybody was sent back to Hollywood with canceled contracts. Months later, she was called to resume filming but by then she had signed with Warner Bros. and could not finish the film. She was replaced by Abbe Lane and her scenes were re-shot.
Arthur Kennedy had begun filming when the money ran out and shooting had to be discontinued. After the funding was finally found, Kennedy was working on another project and was replaced by Frank Lovejoy.
The production took place over two different periods; the first one in Brazil, directed by Budd Boetticher, was too complicated because of the sick actors and crew members related to the tropical settings, and also climatic issues. As a result, everyone returned to the USA and the production resumed the next year, now directed by William Castle, since Boetticher had been attached to another movie in the meantime.
Glenn Ford left the shooting because of the climate and was fined nearly two millions of dollars by the production.