Donald Hamilton's 1960 spy novel "Death of a Citizen" was his first in the long-running series to feature assassin Matt Helm - and it perfectly sets up the protagonist's transition from a normal US citizen into a cold-blooded World War II assassin. Helm was a special agent for the US Government during the Second World War but he turned his back on this bloodthirsty past to start a family in Santa Fe, New Mexico, only for his daughter to be kidnapped by a former colleague. Angered and emotionally distraught, Helm resumes his role as a merciless assassin in Hamilton's brilliant series - books that have been considered a far-more realistic portrayal of the espionage world than Ian Fleming's Hames Bond novels.