The comedy-sitcom Brooklyn Nine-Nine may centralize on several police detectives tackling crime, but there is so much more at the heart. One of the themes: friendship. When you ask fans what their favorite pairings are, some will say Jake (Andy Samberg) & Boyle (Joe Lo Truglio); others may say Jake & Rosa (Stephanie Beatriz). But one pairing that fans have grown to love is Amy (Melissa Fumero) & Rosa.

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The Sleuth Sisters' have a unique friendship as it is one we have personally got to see grow on-screen. From Amy comforting Rosa to their dress shopping trip, here are their top 10 friendship moments.

Rosa Admits to Having Amy's Back (S1 Ep9)

Amy smiling widely and Rosa looking at her

Compared to their other relationships, Rosa and Amy were not as close in season 1. Where Amy is loud and organized, Rosa is more quiet and outgoing. They didn't have anything in common so their interactions outside of work were few. However, "Sal's Pizza" proved Rosa cared for Amy after she told her she had her back.

Amy gets jealous when she finds out that Rosa was offered a promotion. When Rosa asks why she's being snarky, Amy admits she feels like she has to compete with everyone for roles. Rosa tells Amy that this isn't the case anymore as they have to have each other's backs. Amy smiles in appreciation when Rosa confirms she would always have her back.

Ruining The Vulture's Birthday (S3 Ep4)

"The Oolong Slayer" sees Amy and Rosa team up to plan The Vulture's (Dean Winters) birthday party. Rosa thinks it would be a good opportunity to mess with the detective, yet Amy struggles with the idea because of her authority issues.

Amy and Rosa then become frustrated when Pembroke continues to hound them about the party. However, they find the perfect way to get revenge when Amy searches his Facebook profile. They discover that Pembroke is in a band and decide that he should perform at his own bash. Rosa calls Amy an evil genius adding that the next time she wants to hurt someone, she will go to her for help. Amy jokes that this is the nicest thing Rosa's ever said to her.

Amy Comforts Rosa (S4 Ep4)

Amy comforting Rosa in Brooklyn Nine Nine

Rosa and Amy's friendship takes a big step in "The Night Shift" when Rosa confides to her about Pimento (Jason Mantzoukas). At first, Amy gets annoyed with Rosa after she ditches her with a heavy workload. When Amy discovers that Rosa has been lying about her whereabouts, she confronts the detective. However, she is surprised when Rosa begins crying.

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Rosa tells Amy that she is worried about Pimento since he hasn't shown up "at their spot". Amy doesn't do very well consoling her the first time but makes up for it in the end. She tells Rosa that if she ever needs to vent or just wants the company, she would gladly be there. Amy also volunteers to do her paperwork, which Rosa appreciates.

Teaming Up During the Heist (S4 Ep5)

The fourth round of the Halloween Heist sees Amy and Rosa team up to try and win the plaque. Amy is delighted with the partnership when Rosa begins using the codenames from her binder - inspired by The Baby-Sitters Club. Amy's even surprised that Rosa read her suggested reading of "Kristy's Big Day".

The episode also reveals that Amy and Rosa were responsible for the pizza distraction, with Rosa swiping the plaque among the chaos. Amy then admits she wishes the night wouldn't end when Rosa compares their friendship to their own baby-sitters' club.

Rosa Teases Amy (S4 Ep8)

Amy and Rosa's friendship takes an amusing turn when Rosa begins to tease Amy for calling Holt (Andre Braugher) dad. When Holt and Kevin (Marc Evan Jackson) come into the precinct with a math problem, they ask Rosa and Amy to help them solve it. Rosa laughs when Holt fires Amy for agreeing with Kevin.

Rosa then begins to tease Amy for calling Holt "their dad". When Rosa says Holt needs to spend some quality time with Kevin, she finds it amusing that Amy cannot contemplate this. She continues to wind Amy up further when Holt admits Rosa was right, teasing her to the point that Amy has to run away.

How Well Rosa Knows Amy (S4 Ep18)

Stephanie Beatriz and Andy Samberg in Brooklyn Nine-Nine - For entry Rosa helps track Amy down

Fans first discovered how well Rosa knew Amy when she revealed 'the double-tuck' (Det. Dave Majors). They also see it "Chasing Amy" when Rosa helps Jake track down Amy after she runs out on the practice-sergeant exam.

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Rosa advises Jake to think of her as a perp as he struggles to work out her whereabouts. She helps by figuring out that Amy would have visited the Department of Records because that was Kylie (Sarah Baker) worked. When they do manage to find her, Rosa then advises Amy to get to the exam whilst she helps Jake. She looks happy to hear that Amy had aced her exam.

Choosing Amy's Wedding Gown (S5 Ep18)

Amy and Rosa team up on a case after a series of robberies. Rosa notices Amy's strange behavior after she refuses to let her use her laptop. She is quick to spot the reason when she catches Amy glancing at the wedding gowns. When Rosa asks her why she's being hesitant, Amy admits she hasn't had time to look because her new role is a priority at the minute.

Rosa decides to get Amy pumped again for the wedding, encouraging her to try on wedding dresses. She also convinces Amy to carry on looking for the perfect dress after she was about to settle for the first one she tries on. It's a great moment to watch as Rosa reassures Amy that she is a great cop and leader.

Amy's Bachelorette Party (S5 Ep19)

Amy drunk and yelling at her party

In "Bachelor/ette Party" Rosa is seen attending Amy's hen night. One of her first duties as a bridesmaid is to burn the party gift Hitchcock (Dirk Blocker) and Scully's (Joel McKinnon Miller) party gift. This episode also reveals how close Amy and Rosa are.

Rosa had admitted to saying I love you to four people ("Boyle-Linetti Wedding"), but she seems to have gotten more comfortable with expressing her feelings as she says it to Amy. Rosa is also part of the scheme to steal the wedding singer's contract, helping Amy get away from her ex-boyfriend in the process. The group then celebrate Amy finally "breaking a rule".

Amy Fixes the Toilet for Rosa (S5 Ep20)

The episode "Show Me Going" sees how much Amy cares Rosa when she responds to an active shooter call. Amy and the rest of the squad are sitting on tenterhooks whilst they wait for Rosa. She decides to fix the squad's toilet since Rosa had been complaining about it before the call.

Amy is seen to get frustrated with the task, smashing the toilet in anger as she proves unsuccessful in fixing it. She continues to work on it after Gina reminds her that she started it for Rosa. There is a nice moment at the end when Rosa allows a toilet-soaked Amy to hug her.

The Creation of The Sleuth Sisters (S5 Ep21)

The episode "White Whale" reveals one of the first cases Rosa and Amy worked on together as an old enemy reappears. Rosa believes she was at fault for allowing the perp to escape the first time, but Amy reveals that it was hers. After explaining why, Amy has to watch as Rosa storms off to chase another lead.

Amy attempts to get a reaction out of Rosa. Whilst she tries engaging with small talk, she comes up with the name "The Sleuth Sisters"; a name the fandom now uses when references the pair. She then dislocates her knee trying to chase down their suspect, which Rosa scolds her for. Rosa then admits that she is annoyed at Amy for lying to her. The episode ends with Rosa and Amy making up, performing their secret handshake.

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