Detective Boyle’s new romance has upped his swagger, but Jake intervenes before his colleague goes “Full Boyle” and gets too serious, too soon, with his girlfriend. Meanwhile, Rosa and Amy…

Jake and Charles investigate a dangerous serial killer. Holt continues to spar with his rival, Commissioner Kelly. Terry finds out about whether or not he has passed the lieutenant’s exam.

Jake invites his newly discovered half-sister to stay with him in New York, but when he and Amy realize she’s a bit of a nightmare, they must find a way…

The precinct packs up and heads to the Tri-State Police Officers’ annual Cop-Con, which is usually the Nine-Nine’s excuse for a big annual party. But the squad’s fun is threatened…

When an unstable detective returns to the Nine-Nine after years undercover, Jake doesn’t know what to make of him. Meanwhile, Charles’ rebellious behavior pits him against the precinct’s custodian, and…

It’s the day of Gina and Charles’ parents’ wedding, and the whole squad is given a job to fulfill for the ceremony. However, Jake and Amy get sidetracked chasing a…