The friends are listening to Chewoo's story about a sunken treasure ship at the bottom of Greenit's ocean. Yoohoo and his friends decide to look for the ship and they use Roodee's robot fish to lead the way. While on their treasure ship hunt they come upon many sick ocean creatures.

Amongst the group of friends Yoohoo has naturally taken the place as the leader. One day, Lemmee exclaims that he also wants to be the leader. Chewoo, Pammee, and Roodee decide to hold a tournament to pick a leader among the two. In the end, Lemmee wins and becomes the leader. However, the friends cannot stand Lemmee's leadership because he always has to do everything his way.