The fourth instalment in a unique series about a special group of kids training in the ways of the samurai. Yoshi is keeping a secret from the other samurai kids and when Kyoko is kidnapped by an evil enemy from Sensei Ki-Yaga's past, it may prevent the samurai kids from rescuing her.

Kyoko has been kidnapped. Why would Secretary Lu Zeng, advisor to the emperor, want to kidnap a samurai kid? Sensei believes Lu Zeng has set him a challenge to settled old scores. But Niya thinks Lu Zeng's motives are more sinister. Sensei and the Little Cockroaches must act quickly. With the help of the Lin people, they set off on a daring search-and-rescue missing. Does Lu Zeng want Kyoko for one of his experiments? Will they get to her in time?