Never Kill A Client by Brett Halliday

A seasoned private detective takes a lucrative job protecting a nervous, high-profile client who’s receiving threats, only to have the man murdered under his watch. Branded a likely suspect and squeezed by both cops and crooks, he dives into a tangle of blackmail, double-crosses, and high-society secrets. Racing through nightclubs and penthouses, he pieces together a scheme meant to frame him, exposing the hidden motives and the killer behind the setup to clear his name.

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