Mark asks Callie to take their relationship to the next level, but his romantic gesture is threatened when her psychotic, prankster ex-boyfriend returns to win her back.
Lady Hoo-Ha, America's most adored pop star, goes zombie, and her many devoted fans follow suit. Mark befriends one of the newly zombified, and Randall doesn't take it well.
A rabid Bat Boy takes a bite out of Mark, transforming him into New York City's latest superhero. With Koala Man's help, Mark wages war on the city's criminal underworld.
Callie is promptly promoted after turning into a man, causing strife in her relationship. The gender politics are further frustrated by a trip to Atlantis.