For the film's English dub, Cameron Mitchell dubbed not only himself, but also Georges Rivière and Antonio Casas.
Georges Rivière is dubbed by the other actor in the French language version.
Julio Peña (Doctor Stevens) is dubbed by well-known voice actor John Stephenson.
The first Western film directed under Sergio Corbucci's real name. He used an alias previously. Most of the crew also used their real names as well.