Amy returns from maternity leave. Jake and Rosa work a difficult case.

Gina invites Jake and Terry over to her new place. Holt takes an interest in Nikolaj's education. Rosa rejects Amy's offer of a helping hand.

When the FBI takes over a high-profile case, Jake keeps digging. Amy and Rosa negotiate with O'Sullivan and the police union.

Captain Holt and Amy manage an understaffed precinct. Jake and Charles investigate.

Amy and Jake hear conflicting stories as they investigate a sexual assault accusation. Holt refuses to believe an old nemesis is really dead.

The squad suspects an inside job when guns and cocaine connected to a notorious crime boss go missing from the Nine-Nine.

After Gina makes a life-changing decision, she bestows a series of gifts on the squad. But first, an interpretive dance ...

A visitor from Latvia causes Charles and Jake to investigate Nikolaj's family. Holt and Amy bring in famed forensic scientist Dr. Yee to help close a case for Rosa.

Jake and Terry go undercover at a costume-packed fan convention when their favorite fantasy author reports his much-anticipated manuscript stolen.

Jake is assigned a lowly graffiti case as punishment for being late to roll call.

Jake's unsolved cases pile up and the other detectives fear that his losing streak will rub off on them, while Amy must run an at-risk youth program.

When Jake's favorite pizzeria is burned down and the fire marshal suspects the owner, Jake steps outside his jurisdiction to catch the real arsonist.

On his first task back in the field, Terry takes advice from Jake on controlling his emotions to infiltrate and bust a steroid trafficking ring.

When Jake's building goes co-op and he must pay nearly a half million dollars to keep his apartment, he desperately seeks Gina's help.

When Charles makes Jake his best man, it means cake tasting, choosing flowers and convincing fiancée Vivian that Charles doesn't want to move.

Amy gears up to meet Jake's mother on his birthday, but the celebration takes an unexpected turn. New body cameras prove embarrassing for Boyle.

As Jake struggles with his first case back at the precinct, he encounters Jess Day, who is visiting New York, and enlists her to help him find his suspect. Meanwhile, Holt researches ways to increase office morale and Amy tries to figure out why Rosa keeps taking such long breaks. The crossover continues on New Girl S06E04 Homecoming (II).

Charles enlists Jake's help in tracking down his son's favorite toy for Christmas, and the two find themselves accidentally facing off against a Latvian criminal ring as a result. Back at the precinct, the team gears up for their annual Christmas carol competition against their sworn enemy: the MTA.

Jake and Gina attend their 20th high school reunion. Back at the Nine-Nine, Charles helps Rosa with her love life.

While celebrating their first anniversary, Jake and Amy realize they've had a communication breakdown over a major life decision.

Jake and Amy create a system to balance work and childcare and Rosa gets a new houseguest.

The team turns on Jake for delaying an autopsy report by flirting with an attractive medical examiner, who turns out to be more than he bargained for.

Jake's dream day with his hero, a former crime reporter, turns nightmarish when his comments about Holt and the precinct go "on the record."

Holt's nemesis heads the precinct inspection, while Terry readies for his vasectomy and Charles needs a date for his ex-wife's engagement party.

When his relationship with Sophia gets in the way of her work, Jake tries to help, Wuntch needs Holt's help, and Charles wants Gina's blessing.