Why did Captain Holt (Andre Braugher) and Madeline Wuntch (Kyra Sedgwick) hate each other in Brooklyn Nine-Nine? Not known for showing off his emotions, especially at the beginning of the show, the 99th Precinct leader is typically calm and collected. However, engaging in petty prank war isn't exactly below him, especially when it involved his arch-rival, Wuntch.
Introduced in Brooklyn Nine-Nine season 2, Wuntch's first appearance was in episode 2 titled "Chocolate Milk" in which she conducted an assessment in the 99th Precinct. It didn't take long for viewers to realize that there's something odd between the pair as they immediately slung insults at each other. Holt proceeded cautiously with the evaluation, while Wuntch took every opportunity to verbally taunt him. In the end, the Captain, motivated by Amy Santiago's (Melissa Fumero) outburst at him for engaging in Wuntch's unprofessional behavior, groveled to get a passing grade and avoid being transferred to a different precinct.
Since then, each time Holt and Wuntch saw each other in subsequent Brooklyn Nine-Nine episodes, they did not miss the opportunity to make each other's lives a living hell. They've kept their antics verbal — with no physical altercation — but sometimes resorted to professional sabotage to draw the ire of the other. What really started their intense, more often than not childish, rivalry?
Holt explains to Amy during Wuntch's evaluation in Brooklyn Nine-Nine season 2 that they were originally friends during the early stage of their careers. At one point, Holt was up for a big promotion that would've fast-tracked his career and Wuntch was going to write him a glowing letter of recommendation. However, she supposedly torpedoed him by coming up with the opposite. Holt chalks this up to a previous encounter when Wuntch seduced Holt, only for him to blurt out that he was gay, which essentially humiliated her. Assuming that the reason why he was passed up for the promotion was because his former friend backstabbed him, Holt retaliated, resulting in Wuntch having a string of grievances against him. Amy gets to the bottom of the whole situation by looking for the controversial recommendation letter, discovering that Wuntch did put a good word for Holt despite what happened to them.
Obviously, Holt and Wuntch could've mended their relationship if they were only willing to apologize for their crimes against each other, but Brooklyn Nine-Nine sustained their rivalry throughout the years. As she rose through the ranks at the NYPD, Wuntch used her power to get back at Holt. She forced him out of the 99th Precinct at the end of season 2 by promoting him to become the Head of Public Relations of the NYPD. Most recently, Wuntch demoted him after finding out that he became a detective without serving the correct amount of time as a regular officer. Meanwhile, Holt remained annoyed by her presence — always trying to come up with better revenge tactics each time their paths crossed.
While the pair has had a tumultuous relationship, they proved a couple of times that they're willing to work with each other for the greater good. They teamed up to take down the corrupt NYPD Commissioner John Kelly (Phil Reeves) — albeit that Jake Peralta (Andy Samberg) had to be creative to make sure that they didn't backstab each other and compromise the case. Holt and Wuntch's running rivalry was cut short when the former died unexpectedly in Brooklyn Nine-Nine season 7, episode 7, entitled "Ding Dong." This doesn't mean, however, that viewers won't see Wuntch back in the show again, as she can always factor in flashbacks given that she and Holt have a history.