Preoccupied with his romantic plans for Callie, Mark is convinced the evacuation of the entire office staff to hide from a disgruntled former employee is all an elaborate April Fool prank on him.
Mark becomes a masked crimefighter after he's bitten by a rabid Bat-Boy. With the help of his loyal sidekick, Koala Man, Mark wages war against New York's criminals and their catlike leader.
A zombie rock star has made being one of the living dead the latest fad, giving Grimes what he imagines to be a dream job, while Randall is jealous of a new zombie Mark is helping adjust to the "z" lifestyle.
Mark is dismayed by a radical step Callie makes to get a new job, while a misunderstanding has Leonard, Randall, Grimes, and Twayne arguing which is Mark's best friend.
In honor of Twayne's 10-year anniversary of running the D.O.I., Callie and the crew throw him a Roast. But when Mark's attempt at edgy humor goes too far, Twayne quits, leaving Mark in charge. Before his first day as boss is up, Mark makes a management mistake so catastrophic that it almost destroys New York City.moreless
Randall's powerful new arm gets him a job at the Department of Integration, which needs a ringer for a big intramural football game; and the move could send Mark to the second string.
A miniature arsonist in Mark's custody escapes up Twayne's nose, forcing Leonard, Grimes and Mark to make themselves smaller for a manhunt inside Twayne's body.
The surprising return of Mark's college girlfriend forces he and Callie to confront issues about their relationship, while Leonard seeks admission to an exclusive club.
Leonard and Twayne scheme to cash in on a transformation suffered by the zombie Randall, while Mark's own efforts to help lead to an odd second job.
Mark's medical condition may offer the solution to business woes faced by Callie and her father, while Grimes becomes the legal guardian of a teen idol.
Callie replaces Mark with an evil clone in order to win the office bowling tournament, only to have the scheme boomerang on her. And Twayne's new assistant gives Leonard an opportunity to seek his dream career.
Putting on a magic ring Mark finds in Leonard's desk activates an old marriage contract, while a side effect makes Callie lavish affection on a co-worker. But Twayne knows the dark secret of the last person anyone would suspect!
Mark counsels Twayne who has issues about being cast in a key role in the demon End Of Days celebration, only to become suspicious the event may not be the harmless ceremony it's supposed to be.
Grimes has a surprising reaction to the end of a hit TV series, while Callie is pressured by her father to become the new ruler of Hell.