Detective Jake Peralta, Captain Raymond Holt, and the rest of the squad at Brooklyn's 99th precinct have proven over the last seven years that they're capable of putting away any bad guy that crosses their path - they've also proven that they can leave their loyal fans dangling with an epic cliff-hanger finale.
In the seven seasons that Brooklyn 99 has graced the airwaves with their comedy, six of them have ended with cliff-hangers (the most recent season being the only exception). The cop-sitcom has proven year after year that they're masters at making their fans crave more.
Crime & Punishment, Season 4 (8.6)
Despite being the lowest-rated out of all the season finales, the episode to close out season 4 arguably has the biggest cliff-hanger of them all. Jake and Rosa have been set up by a dirty-cop named Melanie Hawkins and stand trial for crimes that they didn't commit. During the episode, the 99 does everything they can to prove that Hawkins is dirty in order to win Jake and Rosa their freedom... but at the last second they get tricked by Hawkins (again) and the end result is Jake and Rosa being sentenced to prison. Not only did audiences have no idea how Jake and Rosa were going to end up, they'd have to wait several months to find out.
Charges and Specs, Season 1 (8.9)
The season one finale threw everybody for a loop when the opening scene announced that Jake had been fired from the NYPD. The episode then jumps back a week in time and explains how Jake has been investigating somebody for money-laundering, but the NYPD Commissioner tells him to back off - which, of course, Jake doesn't.
He then gets himself caught and is put on trial where it'll be determined if he gets suspended, but luckily he finds evidence that he was correct about the money launderer and plans to present it at the trial to prove his innocence. However, Jake ends up not presenting the evidence and gets himself fired instead... because the FBI want him to go undercover and spy on a crime family with his cover story being that he was fired.
Greg and Larry, Season 3 (9.0)
The last four episodes of season 3 dealt with the fact that a notorious crime boss, Jimmy Figgis, was trying to kill a member of the 99, Adrian Pimento. This results in Pimento going into hiding and the rest of the 99 trying to bring down Figgis, which includes finding a mole in the FBI who is actually on Figgis' payroll. Unfortunately, the mole turns out to be Captain Holt's old friend, Bob Andersonn, a man who they thought was helping them find the mole in the first place. After Bob briefly holds Holt hostage, the 99 rescue their captain and eventually get Bob to confess everything he knows about Figgis' operation... which results in Figgis calling Jake and Holt and telling them that he's going to murder them both, resulting in the cliffhanger of Jake and Holt being placed in the Witness Protection Program as 'Greg and Larry'.
Johnny and Dora, Season 2 (9.1)
Jake and Amy had been struggling with their feelings for each other for two whole seasons when it finally came to a head during this episode. With the sexual tension already rising between the two detectives, it reaches a boiling point when Jake and Amy have to kiss while they're undercover on a mission, making things awkward between the two of them. Matters only get worse when Deputy Chief Wuntch decides to transfer Captain Holt to the Head of Public Relations and kicks him out of the 99 for good. Holt, having been bested, announces to the squad that he'll be leaving... prompting Jake and Amy to kiss and get together, for reals, right before their new captain arrives.
Suicide Squad, Season 6 (9.1)
Captain Holt was devastated when he wasn't chosen to be the new NYPD Commissioner at the beginning of season 6, so he spent the entire season doing everything he could to bring down the new Commissioner, John Kelly. Unfortunately, Kelly was able to counter all of Holt's moves... until Jake finally decided that in order to beat a monster, they had to team up with monsters. The season 6 finale brings three of the 99's worst enemies back as they team up with the precinct to bring down Kelly once and for all.
The team carries out a heist to expose Kelly and the unethical/illegal policies he's implemented, but in a twist it seems as though the 99's old enemies turn on them in order to cut a deal with Kelly instead. However, at the last second, the enemies pull a double cross and end up getting all the information they need to kick Kelly out of office. Unfortunately, the season ends with the new interim Commissioner bumping Holt down from a captain to a beat cop.
Jake & Amy, Season 5 (9.2)
While the season 2 finale saw Jake and Amy get together for the first time, it was the finale three seasons later that saw them make the ultimate commitment to their love for one another - their wedding day. Just like any typical sitcom wedding, the day includes a million different problems and obstacles that ultimately ends with the wedding being canceled due to the fact that a criminal Amy put away placed a bomb at the wedding venue. In order to salvage the night, Charles throws together a beautiful ceremony outside of the precinct and Jake and Amy are able to tie the knot after all, with all of their friends and colleagues there to enjoy it with them.
Lights Out, Season 7 (9.3)
The most recent season finale saw Brooklyn's best precinct tackle two obstacles at once - a city-wide blackout and Amy simultaneously giving birth. The show had been leading to Jake and Amy having a baby all season, but nobody was expecting their child to be born at the same exact moment a black-out hit all of New York City. Rosa and Amy try to stay calm and collected while they also coordinate all of the cops in the area, Jake and Charles try to make it back to the precinct to get to Amy since they were in the middle of a call when they find out Amy is in labor, and Terry and Captain Holt get themselves locked in the elevator for the entire episode. Despite all of the craziness, Jake and Amy make it to the hospital and welcome their son, Mac, into the world.