Over the years, Brady has developed an unusual sleeping habit - he becomes a sleep ninja and performs impressive karate moves on Boomer in his sleep. Disgruntled Boomer decides to distance himself from his ninja bro and moves into his own apartment.

The kings want to cheat when Lanny forces them into a throne-threatening King Challenge. They convince Mikayla to help them, but her plan to have Boomer and Brady swap bodies with her two best Fight School students goes horribly wrong.