Robert throws a party for the Dunder Mifflin staff at his house before he sells it because of his divorce. At the party, Erin and Dwight agree to flirt with each other to make Andy jealous, and Jim tries in vain to duck out early.
In Tallahassee, Dwight and Todd Packer try to romance Nellie to get the VP position, while Jim wonders if a colleague is trying to hit on him. Back in Scranton, Val's boyfriend shows up with a message for Darryl.
Jim tries to warn Dwight that he's going to be fired after Robert rejects the Sabre Store idea, but he refuses to listen. Meanwhile, Darryl and Toby try to sell cookies to Kevin, and Erin tells Andy she's not coming back from Florida.
Andy goes to Tallahassee to tell Erin that he loves her and needs her to return to Scranton. Meanwhile, Nellie shows up in Scranton and tries to claim Andy's manager position by offering everyone raises.
Andy and Erin return to Dunder Mifflin, only to discover that Nellie has taken his job and office and refuses to give them up. Meanwhile, Ryan becomes jealous after Pam tries to play matchmaker for Kelly.
Dwight and Jim fight with the Syracuse over a client after Robert shuts down the Binghamton branch, and Andy sees an opportunity for revenge. Meanwhile Robert tries to figure out the contents of a drunken voicemail to Nellie.
Dwight and Andy are intimidated by the office's newest additions, who are considered younger versions of themselves. Meanwhile, Andy tries to make Nellie's life miserable, and Angela tries to get rid of one of her cats.
After Roy's wedding, Jim and Pam wonder if they still have any secrets they're hiding from each other. Meanwhile, Clark tricks Erin into a "news audition," and Dwight challenges Nellie's new charity initiative.
When Jim convinces Dwight that the building is unsafe, Dwight rents a bus and sets up the office inside. Nellie asks for Andy's help in adopting a baby. Meanwhile, Jim tries to make Pam happy with some pie.
The office trains Dwight to sell to a female client without being offensive--only to discover that the client is Jan Levinson, Angela and Oscar both think the senator is cheating on them, and Jim has trouble on an important conference call.
Angela orders a hit on Oscar for cheating with her husband, the office makes a tower with their customer complaint cards, Jim wines and dines Stanley and Phyllis in exchange for a favor, and Pam begins her mural.
Dwight puts together a Pennsylvania Dutch-themed office Christmas party, but he ends it abruptly because Jim has to leave for his other job. Meanwhile, Erin seeks comfort from a co-worker after a disappointing text from Andy.