It's a gloomy day at Greendale Community College, and the student body is gathered for the grand opening of Shirley's sandwich shop. Alone in the hallway, Garrett retrieves a few items from his locker. When he bends down to pick up a folder he's attacked...by the Ass Crack Bandit!
Dean Pelton quickly organizes a press conference to ensure the many news publications of the Greendale campus that there's nothing to worry about; the Ass Crack Bandit hasn't been active for over a year. In private, the Dean informs the Greendale gang that the Ass Crack Bandit sent him a letter to accompany the crime. From the letter, it becomes clear that the Ass Crack Bandit is back on campus, and that he's determined to strike again. Luckily, Professor Duncan returns to assist with the criminal profile.
Jeff and Annie kick off their own investigation, and Annie quickly determines that, due to the timing of the Bandit's previous attacks, he must have taken a shortcut through the teacher's lounge. Is the Ass Crack Bandit a member of the Greendale faculty?
That evening, Troy is attacked by the Ass Crack Bandit in the study room. It's officially a crime spree now, and Annie discovers another note at the scene. Annie suggests to the Dean that the Bandit may be a teacher, but the Dean won't hear it. Annie is frustrated, but Jeff assures her that he'll assist with her investigation.
Nearly a week later, the entire campus is gripped by the return of the Ass Crack Bandit. While analyzing the Bandit's notes, Jeff realizes that the letters contain Dave Mathews lyrics. If their hunch is correct, then Annie and Jeff's search for a faculty member who likes Dave Matthews limits the pool of suspects considerably.
That afternoon, the Ass Crack Bandit strikes again during an Ass Crack Bandit safety demonstration. Jeff and Annie continue their investigation into faculty Dave Mathews fans, but the search leads to nothing but dead ends. Finally, the team gets a break: the Ass Crack Bandit calls the Dean, and they trace the call to the stables (which Greendale has, apparently).
Jeff and Annie rush to the stables to find Starburns, who is apparently not dead after all. After an interrogation, Starburns confesses to being the Ass Crack Bandit. The Dean holds a press conference to announce the capture, and announces that Greendale will be hosting a "We Caught the Ass Crack Bandit" party that evening.
Later that night, the party is in full swing. Still, Annie and Jeff aren't convinced that Starburns is the real perpetrator. He doesn't have access to the faculty lounge, and he doesn't even know who Dave Matthews is. Their suspicions are confirmed when the Bandit strikes again during the party. Annie suspects that Professor Duncan may be the real Bandit, until someone drops a quarter in his butt crack at the party. Jeff and Annie chase after the perpetrator, but they lose him in the hallways.
Moments later, Shirley informs the gang that Pierce has passed away. The news puts an end to the festivities and the investigation. For now, Annie and Jeff will just have to walk away from the cold case. The Ass Crack Bandit is still out there, and it could be anyone...
While Greendale is terrorized by the resurgence of the notorious Ass Crack Bandit, Jeff and Annie painstakingly investigate the crime spree.