The Fourth Protocol by Frederick Forsyth

A tenacious MI5 officer uncovers a clandestine Soviet plot to assemble and detonate a compact nuclear device on British soil to sway an election and splinter NATO. As the bomb’s components are smuggled in piece by piece and a deep-cover operative prepares the device, he battles internal turf wars, political meddling, and KGB rivalries. The investigation builds to a race against time that thwarts the attack, exposes a hidden traitor, and reveals how far covert powers will go to manipulate a nation’s democratic fate.

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