Zero Sum
Returning to Tokyo in 1982 after a decade of mercenary work in the Philippines, a young John Rain learns that the killing business is now controlled by Victor, a half-Russian, half-Japanese sociopath who has ruthlessly eliminated all potential challengers. Victor gives Rain a choice: kill a government minister or die a grisly death. But the best route to the minister is through his gorgeous Italian wife, Maria, a route that puts Rain on a collision course not only with Victor but with the shadowy forces behind the Russian's rise to dominance—and the longings of Rain's own conflicted heart.
It's a battle between kingpin and newcomer, master and apprentice, a zero-sum contest that can only end with one man dead and the other the world's foremost assassin.
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Barry Eisler
Barry Eisler spent three years in a covert position with the CIA’s Directorate of Operations, then worked as a technology lawyer and startup executive in Silicon Valley and Japan, earning his black belt at the Kodokan Judo Institute along the way. Eisler’s award-winning thrillers have been included in numerous “Best Of” lists, have been translated into nearly twenty languages, and include the #1 bestsellers The Detachment, Livia Lone, The Night Trade, and The Killer Collective. Eisler lives in the San Francisco Bay Area and, when he’s not writing novels, blogs about national security and the media.
John Rain
John Rain consists of eleven primary books, and includes one additional book that complement the series but is not considered mandatory reads. The current recommended reading order for the series is provided below.

