CIA agent Mark Stone, played by Kerwin Mathews, has been tasked with protecting the king of Kafiristan after a recent assignation attempt in Rome by a killer that just so happens to have a quirky habit of working in style by unwrapping and popping in a chewy caramel while making a hit.
As far as archetypes go, Mark feels more like the hard-ass detective as opposed to the witty spy hero, which might be disappointing to some and a breath of fresh air to others. However, the more comical spy film playfulness is reserved for Mark’s assistant Costa, played by Venantino Venantini from The Gates of Hell.
The humorously catchy “dup da-ba-dup da-ba-dup” theme music feels like it belongs more in something like Danger!! Death Ray and ends up clashing with Mark's no-nonsense attitude, but the fight scenes, chases, and shootouts that take place in historical Italian locations like The Park of Monsters and the Vatican catacombs are still inventive and enjoyable, despite the distracting music.
An audience pleaser as well as title gratification comes when Mark stumbles upon candy wrappers left over by the killer and states “our killer likes candy”. Though, the candy loving aspect of the killer is more or less a gimmick and doesn't come off as the killer's weakness, as viewers are led to believe.