 Kerwin Matthews, playing a dissolute drifter down on his luck, is stranded in a cheap bar in Spain where he falls for Annette, the pretty daughter of the proprietor, played by Nadia Gray. Nadia Gray gradually shifts the young man s attentions to herself, rather than her daughter, and together Matthews and Gray concoct a plot to help Gray s estranged husband, now a homicidal maniac confined in an institution after a grisly series of killings dubbed "The Acetylene Murders" by the press, out of the mental institution so he can escape from the country.