During Kai's search for the Temple of the Sky, she reluctantly teams up with Ben, Skurd, and Rook at the insistence of Kai's grandfather. As they search, Ben teases Kai about Spanner's telling them they are married in the future, and as he shows her more clues they show more attraction, despite Kai denying Spanner's prediction. Upon reaching the temple and finding the relic inside, the guardian of the temple is an eons old Galvan tasked with protecting a dangerous component of Maltruant by Professor Paradox. Maltruant still succeeds in gaining the second of his three lost component.

While Rook is stuck on graveyard shift at Plumber HQ, his sensei Kundo returns as a cyborg to purge the galaxy of technological influence. Ben and Max take a massive Plumber squadron to stop Yeta, a female Shockquach alien, from continuing her criminal destruction. They later find HQ on lockdown because of Kundo and try to break into the base to give Rook back up. Fistina, the only prisoner, is deputized by Rook so as to help defeat Kundo. Following Kundo's defeat, Rook is effectively promoted to Majestor and Fistina is allowed to go to the academy following her time served.