House of Cards - Stanley Ellin

Hired as a tutor for a madwoman's son, an American expatriate scraps to stay alive
A washed-up heavyweight with dreams of becoming a writer, Reno Davis is down to his last franc when he lands a job as a bouncer at a sprawling Paris discotheque. His first night, he saves a slumming beauty from a pair of café toughs, and she rewards him with a well-paid job tutoring her darling son. But what she really wants is a bodyguard to keep her precious baby safe from terrors real and imagined. Reno's new boss is a mental case, paranoid and delusional, whose lovers have a bad habit of dying violent deaths. But in this case, her paranoia may be justified.

Protecting the boy draws Reno into an international conspiracy that stretches from Paris to Rome to the killing fields of northern Algeria. When the bullets start to fly, this ex-fighter begins to fear that he may be punching above his weight.