Kusanagi, the priceless sword of the Japanese crown jewels, that must be at the coronation of every Japanese emperor, is missing. Danny, a Navy SEAL out of his element, is in London to sell a precious artefact - a gold ingot from an ancient sea wreck off the coast of Japan. Jim Evans, retired whizz kid trader, is young and impossibly rich. Through a chance meeting in a London auction house with Danny he acquires the gold ingot and realises it is just the tip of a huge medieval fortune. Fate, ambition and greed come together in the search for Kusanagi - a prize of such incalculable value that it carves a trail of destruction from Tokyo to London for all those who covet it.