It's Halloween in the office and Andy invites his college a cappella group to perform, which leads to a confrontation with his frenemy Broccoli Rob. Meanwhile, Dwight finds evidence that a madman is loose in the office and tries to track him down, and the first meeting of Jim's new job causes a fight with Pam.

One year later, Dunder Mifflin employees past and present reunite for a panel discussion about the documentary and to attend Dwight and Angela's wedding.