Out of the violent chaos of medieval Japan, a band of men from the mountain provinces rose to become some of the world's most feared warriors. These men trained to perfect their art – a deadly union of martial skill and deception – to defend themselves against the warlords, samurai and bandits who sought to exploit them.

Hundreds of years later their name is a legend whispered down the generations. A select few are still trained in the ancient craft. Fewer still are selected to train at the feet of the most arcane practitioners of the shadow warriors...

Nicholas Linnear is one of these elect. And as the city of New York is terrorized by a ritualistic murderer, he may be the only man who can stop these killings. A ghost, an assassin, guided by honour and tradition: the Ninja.