Twayne and the demons try to infiltrate a secret wizard compound by building a summer camp in 24 hours with Mark Lilly as the head counselor.
Callie's parents reconcile and have a baby; Callie plays guardian to her younger sibling.
Grimes is upset over the end of his favorite series.
Twayne is drafted into Satan's Dark Army; Mark discovers a plot against humanity.
Mark finds a magic ring and Randal is forced to serve as Mark's squire.
Callie makes a clone of Mark; clone Mark decides to get revenge after he finds a cruel message in her diary.
Randall puts Mark's soul up for sale, Grimes pursues his dream of creating a pop music act with a teen sensation.
Twayne throws a company party aboard a cruise ship; Randall gets sick from dangerous pollen.
Callie reveals to Mark that she's been sleeping with other guys.
With Mark working all the time, Randall feels neglected, so he decides that they should spend more time together to decide if they should stay roommates.
With the big company intramural football game coming up, everyone starts getting nervous about the lineup; Randall demonstrates the power of his recently replaced arm and is given a job at the D.O.I. as the team's ringer.
In honor of Twayne's 10-year anniversary of running the D.O.I., Callie and the crew throw him a roast; before his first day as boss is up, Mark makes a management mistake so catastrophic that it almost destroys New York City.
Mark becomes conflicted about his relationship with Callie. He does his best to be understanding, but their love is soon put to the test when they are asked to embark on a dangerous mission to the fabled underwater city of Atlantis.
When the country's biggest pop star ("Lady Hoo-Ha") turns into a zombie, millions of her devoted fans follow suit; Mark befriends one of the new zombies and Randall is forced to deal with his jealousy issues.
After being bitten by a rabid Bat-Boy, Mark becomes a masked crimefighter; Mark wages war against New York's criminals and their catlike leader with the help of his loyal sidekick, Koala Man.
Mark chooses April Fool's Day to ask Callie to take their relationship to the next level, but his romantic gesture is threatened when Callie's vengeful ex-boyfriend returns to win her back; Leonard tries to redeem a winning lottery ticket.