Jake helps Charles reclaim the rights to his sperm from his ex-wife, Amy accidentally breaks Terry's nose after asking for a recommendation, and Gina helps interrogate a suspect who refuses to speak to anyone but her.
Peralta and Holt contract the Mumps while working on a cold case. Terry takes over the precinct in his place, but his ambitious plans ultimately fail. Boyle is sad over the death of his dog, but Diaz doesn't understand it.
Jake comes face-to-face with his old nemesis Doug Judy as he and Amy go on a cruise. Meanwhile, Holt's sister comes to town for a visit, and Diaz and Boyle fight over a rent-controlled apartment which was a crime scene.
On Jake's birthday, his Mom tells him she is back together with his hated father. Meanwhile, Charles has an embarrassing moment with a body cam, and Holt's "Escape the Room" exercise for the Nine-Nine does not go as planned.
Chaos ensues when the Nine-Nine is forced to share their station with the Nine-Eight precinct while their station is closed, and Charles consequently becomes jealous of Jake's old partner, who is an officer in the Nine-Eight.
Trying to get called to a "celebrity" case, Jake tricks Hitchcock and Scully into taking a case that might me more dangerous than everyone thought. Amy, Rosa, and Gina take the day to conquer their worst fears
The precinct gains a new detective who has just completed a 12-year undercover job with the mob, Charles' latest mess prompts the janitors to refuse to clean the precinct, and Gina directs a video for Holt.
While Holt is en route to visit Kevin in Paris, Jake and Amy inadvertently lose his dog. Meanwhile, Charles has laser eye surgery, and the sexual tension between Rosa and Adrian Pimento disgusts Terry.
Terry enlists Jake's help in solving a twenty year old case which his old precinct never let him forget, Charles allows Adrian Pimento to stay at his place and soon regrets it, while Amy, Rosa and Holt attend a class together.
The precinct tries to set up perfect bachelor and bachelorette parties for Adrian and Rosa after they announce their engagement, but Adrian's party falls apart when he tells everyone that someone is stalking him and steals the party bus.
With Adrian off the grid and in hiding, the rest of the squad scramble to track down the sister of Figgis, the mobster behind the operation, and throw a fake funeral to flush out Figgis' hit man.
While Amy continues to work on Figgis' sister Maura on the inside, Jake, Rosa and Holt team up with Bob Annderson to track down the FBI mole. Meanwhile, Gina helps Terry work out the culprit behind a press leak.
After a surprising turn of events in the Nine-Nine's attempt to track down Adrian Pimento's hitman, the precinct drops everything when they suspect Holt is in danger.
The team goes to Florida to help Jake and Holt take down Jimmy Figgis, but their plan falls through due to an unexpected injury and another interruption from Sheriff Reynolds.
Jake, on his first case back at the precinct, commandeers the vehicle of Jess Day, (from New Girl) who's visiting New York. In the meantime, Holt tries to increase office morale and Amy wants to know why Rosa is taking such long breaks.
Amy's father, a former cop, comes to Thanksgiving dinner and Jake tries to impress him, leaving Charles on turkey duty. In the meantime, Holt helps Pimento come to terms with the fact that he can no longer be a police officer.
Terry meets his lifelong hero, a famous author who's received death threats. In other events, Gina tries to choose the location of the Boyle family vacation and Amy sides with Kevin in his argument with Holt over a math puzzle.