Heirs of Cain

In this gritty but generic thriller, long-buried rivalries resurface as two assassins are pitted against each other with predictable results. After engaging in bloody guerrilla warfare in 1971 Vietnam, seven soldiers struggle to return to normal life in the U.S. Forty years later, one dies violently, leaving the words “fallen angels” as the only clue to his killer. Michael Collins, once a notorious assassin known as Cain, left the military behind and became a respectable college professor, but he can't refuse the chance to avenge his comrade by going after Seneca, another member of that select Vietnam group who's now involved in a terrorist plot. Wallace (The Devil's Racket ) raises interesting questions about moral relativism and how trained killers can adapt to civilian life, but the formulaic story overwhelms any hope of real excitement or philosophical inquiry. (May)