Andy assembles the staff to let them know he's going to be the first boss of Scranton to make everyone's Christmas wishes come true. But Stanley is pushing back; he's afraid it's going to be yet another strange thematic Christmas, joining the ranks of a Moroccan Christmas, a Mo Rocca Christmas, a Muslim Christmas, and on and on. In an interview, Jim admits that he gave Stanley tickets to see Lewis Black for his birthday. Obviously the comedian had an impact.
Andy answers questions from the staff and assures each of them their wishes will be met: he'll be Meredith's designated driver; Dwight will get an acre on the moon, etc. In return, Andy's wish is that the team will love his girlfriend, Jessica. Andy gives a few final words of warning: the mistletoe is not an excuse for sexual assault, so stay away from his grandmother.
Kelly offers to Erin to be mean to Andy's girlfriend, but she declines. As they're talking, a somewhat beleaguered Robert California shows up, wishing Erin a Merry Christmas and Kelly a happy Pancha Ganapati. Kelly's never heard of the Hindu festival that takes place each December.
Robert gets a big bear hug from Kevin, who comforts him in the wake of his marital troubles: Robert and his wife have separated. Robert complains to the team about the awful DMS corporate party and how bothersome the Black Eyed Peas were.Andy puts on his Hard Ass hat and brings Dwight and Jim into his office for a serious discussion. Their pranking has gotten out of hand. He informs them that their Christmas bonuses are in jeopardy. If he catches one of them pranking the other, he will give the pranker's bonus to the one being pranked.
Andy's new girlfriend Jessica arrives; Erin greets her with a hug. They're very gracious to one another. Andy emerges and tells Jessica that Erin is an amazing receptionist. Jessica observes that she must be the backbone of the office. Erin then tells an uncomfortable story about having scoliosis as a child, which she follows with a seemingly spontaneous attack of scoliosis. Downstairs in the warehouse, Darryl invites Val to the upstairs Christmas party, telling her to dress up.
Jim notices that Dwight has left his wallet and keys on his desk; he's also left a half composed email open on his computer. He's incredibly tempted to play a prank - but he realizes that Dwight's trying to entrap him. Meanwhile, the party's getting underway. Robert California is pouring shots for the staff. Even the demure Erin gets in on the fun.Jim lays his own trap for Dwight: he pretends to be on the phone with his credit card company and loudly reads the number and security card to them. He secretly notices Dwight writing the numbers down. Dwight uses the information to make a prank phone order for flowers - to Pam from Jim.
Val arrives at the party - dressed to the nines. Embarrassed at being overdressed, she confronts Darryl who apologizes and begs her to stay. Meanwhile, an increasingly tipsy Erin is performing impressions of her office colleagues. Andy pulls her aside and lets her know she should watch her alcohol intake, but Erin tells him to mind his own business. Later, Erin fawns over Andy and Jessica, telling them she hopes they get married. She's obviously drunk. Andy pulls her aside later, and Erin says her Christmas wish is that Jessica was dead. Andy tells her publicly to take her wish back - and to get over the fact that their relationship is over. Erin's belligerent and upset.
Dwight cries out: someone's put a porcupine in his desk and one of its quills has punctured his skin! A crowd gathers. Andy suspects Jim. Jim denies it and pretends to call animal control to have it removed. In the process of answering questions, he tricks Dwight into revealing the porcupine's name - a sure sign Dwight planted the creature in his own desk.Jim finds a defaced picture of Cece and takes it to Andy. Andy suspects Dwight - and thinks about firing him. But it's another trap from Jim. Jim realizes that he may have gone a little too far and backtracks on the implied accusation of Dwight, saying that he may have done it himself by accident.
Dwight takes control of the party music, switching the pop tunes to a heavy metal "Chorus of the Bells." Meanwhile the gifts come out. Oscar gives Kevin a cookie jar; Meredith gives Jim a pamphlet on vasectomies; Ryan and Kelly give Angela a long shirt that reads "Ask, then Touch" on the belly.
Jim checks in on an upset Andy sitting by himself in the breakroom. Andy wonders whether two people who aren't sleeping together can be friends. Jim says yes. But Andy's not so sure after his recent experience with Erin. Andy goes on to tell Jim that he's not going to put his and Dwight's bonuses at stake for pranking. It'll cause too many problems, he tells Jim - and asks him to inform Dwight.
Erin seeks out Kelly: she wants her to inflict some pain on Andy's new girlfriend. Kelly doesn't miss a step, walking straight over to Jessica who's entertaining a group with some stories. She accuses Jessica of farting; it's an immediate buzzkill.Kelly asks Robert, who's tending bar, for another drink. Instead, Robert turns over bartending duties to Oscar and takes Erin for a walk outside. They're both heartbroken. Erin asks Robert for love advice, but he confesses that with two failed marriages and a third headed for divorce he's hardly in position to advise anyone. From the office window, Andy spies Robert giving her a hug.
Dwight is spraying "Jim Is Awesome" on his own Trans Am. He doesn't know the prohibition on pranks is over. Meanwhile, Andy gives a very inebriated Meredith a ride home. On the way he spots Robert dropping Erin off at her house - and again giving her a nice hug. Andy smiles.Dwight pulls a final prank on himself, trying to secure Jim's Christmas bonus. He writes "Idiot" on his forehead in marker, then feigns sleeping at his own desk. He wakes up and acts surprised at how everyone is looking at him. In interview, Jim realizes he forgot to tell Dwight something - but he just can't remember what it was.