Brad Dexter was cast at the urging of Frank Sinatra, who knew Sturges well, because Dexter had saved Sinatra's life when the two were swimming off the coast of Hawaii.
Sturges was eager to cast Steve McQueen in the picture, having just worked with him on the 1959 film Never So Few, but McQueen could not get a release from actor/producer Dick Powell, who controlled McQueen's hit TV series Wanted Dead or Alive.