The Warsaw Protocol by Steve Berry

Former Justice Department operative turned rare-book dealer Cotton Malone becomes entangled in a dangerous hunt for a wartime document whose exposure could unleash a conspiracy to resurrect extremist power; racing across Europe with uneasy allies and facing ruthless adversaries, he uncovers a web of hidden wealth, betrayals, and present-day ambitions rooted in buried history, and must use his wits, contacts, and knowledge of the past to stop a catastrophic plot from coming to fruition.

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