The Kaisho
Years ago, Nicholas Linnear, a.k.a. “the Ninja,” made a promise to his father: If a man named Mikio Okami ever sought his help, he would respond without question, no matter the cost. Now the time has come to fulfill his pledge. Okami is the Kaisho—the boss of bosses of the Yakuza, the Japanese underworld—and in his Venice headquarters, he realizes that he has been marked for death. But the identity of the assassin and the inexorable compulsion that drives him are shrouded in mysticism and madness. Honor bound to protect Okami, Linnear is prepared to make the ultimate sacrifice: a descent into a chasm of knowledge so potent, of dangers so unfathomable, that even if he survives, he will emerge changed forever.
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Eric Van Lustbader
Eric Van Lustbader (born 1946) is a writer of fantasy and thriller novels.
Eric Van Lustbader was born and raised in Greenwich Village in 1946. He is the author of more than twenty-five best-selling novels, including The Ninja, in which he introduced Nicholas Linnear, one of modern fiction's most beloved and enduring heroes. The Ninja was sold to 20th CenturyFox, to be made into a major motion picture. His novels have been translated into over twenty languages.
Nicholas Linnear
Nicholas Linnear consists of seven 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.

