John Kinsdale (Academy Award winner George Kennedy, Cool Hand Luke, The Dirty Dozen) is a devout family man working as a NATO computer specialist in Naples, Italy. When political terrorists kill his entire family, John uses his technological prowess to track and hunt down the cold-blooded killers. Trying to prevent him from taking the law into his own hands are a local police inspector (Raf Vallone), a U.S. military commander (Arthur Franz), and peers MacAllister (Sir John Mills) and Janice (Rita Tushingham). But nothing can prevent John from meting out his bloody brand of grief-stricken revenge.