Secret Treasure New adventure series set in medieval Japan based on Shintaro the master swordsman and his relentless search for his enemies, the black robed society known as the Koga ninja.

On a Tokyo street at midnight, a lonely traveller is passing when a dark figure springs out of the darkness, kills him and begins ransacking his pockets in a hasty search for a bag of gold he was taking to one of the Shoguns ministers.

Stolen Face The first of the 13 ninja of the Koga society is dead after challenging Shintaro to a fight.

Now Shintaro and his young companion, Shusaku, are in search of another challenger.

Track of the Ninja While walking along a dusty road on their way to Kofu, Shintaro and Shusaku notice an express courier in a great hurry and they catch sight of a ninja knife falling out of his pocket.

That night Shusaku is kidnapped.