In the Season 2 premiere, the group reconvene to study for their anthropology class, which is taught by a kooky professor (Betty White). Elsewhere, Jeff navigates the tangled situation with Britta and Annie; and Señor Chang enrolls at Greendale in hopes of joining the study group.
Jeff reconnects with his former law-firm colleagues (Rob Corddry, Drew Carey) and returns to some old vices. Seeing the changes in Jeff, the study group decide to come to his rescue, only to find themselves corrupted in the process.
The group rally around Pierce to offer comfort when his mother dies. Elsewhere, an out-of-his-element Professor Duncan takes the helm of Anthropology 101 after Professor Bauer takes a leave of absence.
A competitive Dean Pelton asks the study group to refurbish an old flight simulator in order to stay on par with a rival college. The gang's efforts take an unexpected turn, however, and it's up to Abed to ensure his friends' safety.
Shirley consults Abed when she decides to make a religious film, but the two end up clashing after Abed reveals his plans to make one, too. Elsewhere, Pierce considers joining a study group with students his own age after he realizes he's the oldest member in his current one.
A campus Halloween party takes an unusual turn after Pierce and some students ingest a hazardous substance, which produces zombie-like symptoms in them. Dean Pelton responds to the situation by quarantining the area with the study group inside, forcing them to fend for themselves.
Abed becomes a "mean girl" to the delight of Britta, Shirley and Annie, whose encounter with a cruel classmate (Hilary Duff) leaves them reeling. Elsewhere, Jeff and Troy find a hidden trampoline, which provides the duo spiritual enlightenment. The change in their personalities doesn't go unnoticed, however, and Pierce becomes determined to get to the bottom of things.
Everyone's a suspect when Annie's favorite pen goes missing, so the group lock themselves in until the thief is found. Jeff leads the investigation, but Abed and Troy aren't as invested in the mystery because they want to go to a nearby puppy parade.
Dean Pelton nabs Jeff for listing a fake class on his schedule, but then a mysterious professor (Kevin Corrigan) emerges to back up Jeff's claim. Curious about the man, Jeff and Annie investigate. Elsewhere, Abed and Troy build a blanket fort of great proportions.
The group go to a bar to celebrate Troy's 21st birthday. Britta and Jeff bicker during the outing, while Shirley goes on a mission to remove questionable photos of herself. Annie gets into character based on her fake ID, and Abed finds a kindred spirit at the bar.
Abed goes on a quest to find the meaning of Christmas after he awakens in stop-motion animation. A worried Jeff and Britta seek help from Professor Duncan, and the group eventually undergo hypnosis to join Abed in his world.
Annie's crush (Greg Cromer) enrolls at Greendale, and the study group consider adding him---as well as Señor Chang---to their ranks. Elsewhere, Shirley has big news for the group now that her ex-husband (Malcolm-Jamal Warner) is back in her life.
Annie stages a play with an anti-drug message at a local middle school, but the production hits a snag when Pierce lets his creative side run wild. As the conflict intensifies, Senor Chang unexpectedly steps in to restore order.
Abed and Jeff plan a game of Dungeons and Dragons to boost the spirits of a lonely student (Charley Koontz). But when Pierce learns he's been omitted from the game, he barges in and takes control of the situation.
Troy and Abed become romantic rivals when they both pursue the college librarian. Elsewhere, Britta befriends a student who she presumes is a lesbian; and Professor Duncan invites himself over to Jeff's place.
A brush with death prompts Pierce to bestow final gifts upon his pals. Britta receives a blank check to donate to a charity of her choice; Jeff has a chance to meet his father; and Troy meets his idol, LeVar Burton. But the gifts soon turn out to be more than the gang had bargained for.
Greendale holds student elections in preparation for a visit from the vice president. The contest pits Annie, Jeff, Leonard and Star Burns against one another. Meanwhile, Abed befriends a secret-service agent (Eliza Coupe) who's casing the school.
Jeff plans a birthday party for Abed based on "Pulp Fiction," but Abed has his own ideas for the evening. While the study group await the pair's arrival, Abed takes Jeff to a restaurant to re-create scenes from a different movie.
Pierce falls for a mysterious woman (Michelle Krusiec) whom he meets in a wine-tasting class, but Jeff is suspicious of her motives. Elsewhere, Abed takes a class studying the sitcom "Who's the Boss?," while Britta and Troy try their hands at acting.
The group reminisce about fun times in a series of flashbacks, which include a trip to a ghost town, a glee-club performance, and Jeff and Britta's secret trysts. Elsewhere, Troy's monkey resurfaces briefly before disappearing again, and Senor Chang goes after him.
Shirley goes into labor during an anthropology exam, prompting Chang to claim the baby as his and Jeff and Britta to argue over the best way to help Shirley. Elsewhere, Dean Pelton gets caught up in a World Food Festival riot.