Complete story — includes the ending
After a Plumber setup to find out if the team has been masquerading as Plumbers, Ben, Gwen and Kevin are forbidden to fight against the Highbreed threat by Plumbers Magister Prior Gilhil. Gilhil has doubts the Highbreed are even as much of a threat as they claim. Elsewhere, a mysterious powerful new enemy 'employs' a Highbreed to attack the team. Having also tipped off Gilhil, all three are captured by the team's old enemy, Michael Morningstar, now calling himself Darkstar and is wearing a mask to hide his deformed face following the incident in "All That Glitters" and he is the one who manipulated Prior Gilhil and Highbreed.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, List of Ben 10: Alien Force episodes. HTML formatting and reference markers removed. · Content license