At the beginning of the episode, Kevin attacks and steals the powers of the half-human Alan Albright, but is driven off by Ben before he can kill him. Alan reveals that Kevin has already stolen the powers of all of the Plumbers’ Helpers as well as Ben’s old foe Dr. Viktor. Ben, convinced that he must eliminate Kevin for the safety of the Earth, asks Gwen to help track Kevin with her powers. Gwen refuses, and the two argue, which leads to them battling each other; Ben defeats Gwen with Way Big, claiming her sentimentality prevents her from having what it takes to deal with Kevin. Ben then indiscriminately seeks out other villains, attacking them mercilessly in search of Kevin’s whereabouts. Gwen, meanwhile, locates their old enemy Michael Morningstar and asks for his help. Ben and Gwen separately consult Grandpa Max about how to deal with Kevin; while Max encourages Gwen to stay out of Ben’s way, he admits to Ben that his decision to kill Kevin is unlike him.
Gwen and Michael meet with Ben, and Michael reveals that Kevin has developed an addiction to absorbing energy not unlike his own. He then states that the broken Dominus Librium (the device used by Michael to absorb Kevin’s powers in the Ben 10: Alien Force episode “Trade-Off”) has the capability of removing the powers that Kevin has stolen, returning him to his ordinary form. Ben agrees to help Gwen and Michael track down Kevin, but only so that he can kill Kevin himself. Gwen later confronts Kevin at the same New York City arcade where they first met, imploring him to let her help him; Kevin reveals that he has been trying to avoid Gwen to prevent himself from hurting her, but loses control and attacks her, beginning to absorb her powers.
