The Marvelous Misadventures of Flapjack S02 E07 Off With His Hat

When Flapjack helps Captain K'nuckles look for his lost hat on an island filled with chimpanzees, they end up encountering a researcher living among them. With her help, they must reach the "secret meeting place": an active volcano whose crater K'nuckles must cross so he can get his hat back.