Agent X by Noah Boyd
From Booklist
Steve Vail, once an ace FBI agent, now a bricklayer (The Bricklayer, 2009), arrives in Washington to take Kate Bannon, the bureau’s assistant director, to an embassy soiree. But his romantic mission is sidelined by an urgent summons from the bureau: a Russian embassy staffer, code-named Calculus, is offering to name Americans feeding sensitive information to Russian intelligence. But no sooner than the bureau accepts the Russian’s terms, he is spirited off to Moscow, presumably to be tortured into admitting what he has done. Steve and Kate must identify the moles and reel them in before the Russians snuff them. But before that can happen, Vail must solve the many puzzles that Calculus uses to conceal information. Thriller fans get an endlessly twisting plot strewn with chases, gun battles, and explosions. Calculus’ puzzles are engaging, and the bureau’s procedural and bureaucratic thickets sound real.
