Kōshi was made to swallow a ball of poison from the Tenga clan and was told that in a week he will die unless he is given an antidote. Momoko willingly swallows the same poison so that if Kōshi dies, she does as well. Momoko and the other martial artists on their side train for a week, and Kōshi tries to learn a technique of his own, but fails. Kōshi and the others then go to the Tenga clan's main house and must fight several battles to gain the antidote.
