In an attempt to solve an international case, Jake and Rosa are forced to work with a pair of Swedish cops and things get very competitive, very quickly. Meanwhile, Amy and Terry offer to help Gina prepare for a big test and Holt enlists Charles to sub in as his squash partner for an annual tournament.
Jake Peralta and the rest of the squad are dressed formally to unveil the new vending machine. After giving a speech, Jake attempts to break a bottle of champagne over the machine to christen it, but the fluids from the bottle cause a short circuit on the machine's button. Jake assures everyone that the snacks in the machine are still intact, only for the interior of the machine to immediately catch fire. As the squad evacuates the room, Scully cries out that it should have been him instead of the machine.
Jake and Rosa Diaz are at the docks, looking to arrest someone who is reportedly selling counterfeit caviar. Jake asks Rosa for advice on getting Amy Santiago a six month anniversary present, but she refuses as her friendship with Jake does not involve talking about anything not relevant to the cases they work on, and is why she considers him to be her closest friend. Jake and Rosa then manage to arrest the counterfeiter, and discover a large diamond necklace in his possession. In the briefing room, it is revealed that the necklace is a priceless diamond stolen from the Royal Stockholm museum. Captain Holt informs Jake and Rosa that two Interpol agents from Sweden are on their way and asks them to be welcoming. Jake excitedly says that working with Interpol will be the second best thing that has happened to him, behind dating Amy, but jokingly whispers to Rosa that he was lying to Amy. In the break room, Gina Linetti asks Amy and Terry Jeffords if they want used Astronomy textbooks, and immediately throws them into the garbage. She explains that she does not think she will be able to pass her upcoming Astronomy final, prompting Amy and Terry to offer to tutor her for her exam. Holt introduces the Interpol agents Soren Knausgaard and Agneta Carlssonn to Jake and Rosa before taking his leave. Jake attempts to charm them and offer to treat them to food from the food cart outside the precinct, but they turn him down condescendingly, and offend Jake and Rosa by commenting that the precinct is filthy and that Jake and Rosa themselves seem unprofessional. In the breakroom, Holt arrives with Kevin Cozner and asks Boyle if he would like to be his squash partner in a tournament, as Kevin is leaving for Paris for six months. Boyle agrees, but after Holt leaves with Kevin, confides in Terry that squash brings out his competitive side, to the point of eating a squash ball to terrorize his opponents. Terry suggests Boyle have fun, and the latter agrees as he does not want Holt to see him "unleash the beast". Holt informs Jake and Rosa that there has been a development in the diamond case, as they believe there are more stolen diamonds from Sweden in Brooklyn. Jake tells them that he will keep them informed of the investigation, but to his and Rosa's horror, the Interpol agents will be staying to work the case with them.
The next day, Jake and Amy are waiting for the Interpol agents outside the counterfeiter's apartment and attempt to get a jump on the investigation first, but discover that the Interpol agents have actually arrived earlier and already searched the apartment. In the precinct briefing room, Amy attempts to tutor Gina, but the latter is uninterested in what Amy has to say, discreetly leaving while Amy is attempting to teach a mnemonic device to recall the moons of Jupiter. At the perp's apartment, Jake and Rosa have discovered a shipping manifest that was hidden in the back of a drawer, showing a container was transferred to Bay Ridge on October 11. The Interpol agents are skeptical of this lead since the date was over a month ago, and instead have found an invitation to the party of Alvar Gustavsson, a Swedish millionaire with ties to organized crime. Both pairs decide to pursue their respective leads instead. Meanwhile, Boyle and Holt begin their squash tournament at the country club. At the first serve, an opponent claims Boyle's serve was out, prompting Boyle to briefly lose his temper, before nervously repeating that "this is fun". In the bullpen, Terry introduces Gina to Neil deGrasse Tyson, who goes to the same gym as him. Neil deGrasse Tyson tells Gina that if she will give him 2 hours, he promises she will not only pass her exam, but develop a keen interest in Astronomy, but Gina turns him down. He then asks why Gina wanted to learn Astronomy, and she reveal that she thought Astronomy would involve her just naming different moons and planets, leading him to comment to Terry that Gina is going to fail her exam. At the shipping container yard, Jake asks Rosa what Marcus gave her for their anniversary, only to learn that Rosa and Marcus broke up a month ago. Jake asks Rosa why she did not tell him, but she insists that their friendship does not involve divulging personal details. They then find the shipping container they were looking for, but upon opening the container, discover nothing but a pile of fish.
The following day, Jake arrives at the precinct, where the Interpol agents inform him that the party they attended was very enjoyable. Jake asks if they would tell each other when they divorced their own romantic partners, and they confirm that they would as they are very close. They then ask Jake why he smells like fish, and he reveals that he and Rosa spent the whole night cutting open the fishes in the container, only to find nothing. As the agents leave, Rosa is disgusted at how close they are, to the point of actually holding hands while they walk. Jake tells Rosa that he does not believe the Swedish culture of partners being close is a bad thing, causing Rosa to realize that the shipping manifest was written in the day/month format instead, meaning the container was scheduled to arrive on 10th November. At the country club, Holt asks Boyle if he is fine since he is acting erratically, and points out that if they lose another match, they will lose the tournament. Boyle nervously says the important thing is to have fun, but Holt instead says that the important thing is to win. Holt reveals that he invited Boyle to be his partner as he read in an article that Boyle was "Squash's unhinged lunatic", but won 27 matches in a row, and asks Boyle to "unleash the beast." Boyle then changes his attire completely and exhibits a more aggressive attitude, while deriding his opponents. In the precinct, Amy and Terry make one final attempt to teach Gina, this time by using dance moves, which peaks Gina's interest. One hour of dancing later, they ask if Gina is ready for the exam but she reveals that she already took the exam and passed, as after being moved by Amy and Terry's efforts earlier, she decided to actually study and developed an interest in Astronomy. Terry asks why Gina still let them do the dance, and she informs them it was so she could see Terry's pecs, which Terry comments is understandable. Jake and Rosa discover the shipping container, with the diamonds intact. As Rosa tells Jake they should celebrate, she notes that Jake is upset, and he tells her that he is still upset about Rosa not telling him about her breakup. Rosa asks why he would take an interest in her life all of a sudden, and he replies that while he enjoyed only talking about police work when he was younger, they both have important things in their lives that friends should talk about. Rosa then coldly says that must mean they are not friends, as someone begins to drive off with the shipping container while they are still in it.
Jake calls for backup, but the truck pulls into the parking lot and they realize backup will not arrive in time. He and Rosa then use a form of shorthand to communicate their plan, and are able to take down the criminals when they open the container door. At Shaw's bar, Holt and Boyle show Kevin through a video call that they have won the first place trophy. Kevin excitedly says that he looks forward to earning their fourth trophy in a row the following year, but Boyle and Holt reveal they have been banned from future tournaments, as Boyle snapped the second place trophy and threw it into a urinal. Regardless, Boyle and Holt maintain that they had fun. Jake and Amy attempt to gloat over the Interpol agents over the agents being wrong, but to their annoyance the agents instead tell them they had a pleasure working with them. Jake then offers to drink in silence with Rosa to celebrate as they usually do, but she realizes that Jake is still upset, which also upsets her as she maintains that they are friends. Rosa then tells Jake she knows what he should get Amy for a present, suggesting that he make her a VIP at the New York Public Library, since VIPs can stay there overnight. Rosa also reveals that she can help Jake with acquiring VIP status, as her new boyfriend works at the library, also revealing that his name is Tom after drinking several shots of hard liquor.
|Andy Samberg||...||Jake Peralta|
|Stephanie Beatriz||...||Rosa Diaz|
|Terry Crews||...||Terry Jeffords|
|Melissa Fumero||...||Amy Santiago|
|Joe Lo Truglio||...||Charles Boyle|
|Chelsea Peretti||...||Gina Linetti|
|Andre Braugher||...||Captain Ray Holt|
|Dirk Blocker||...||Michael Hitchcock|
|Joel McKinnon Miller||...||Norm Scully|
|Marc Evan Jackson||...||Kevin Cozner|
|Neil deGrasse Tyson||...||Himself|
- The diamond is called the "Köttbullediamant." "Köttbulle" is Swedish for "meatball", a popular delicacy from the country. So the name of the diamond in English would be the "Meatball diamond".
- This episode takes place before "Ava" as Agneta re-arranges dates that happened before Thanksgiving and Jake and Rosa go after a container coming in on November 10. This means that the episode took place between November 10 and November 13.
- Rosa had previously broken up with Marcus in "Into the Woods".
- Terry mentions that Boyle has been wanting to be able to bond with Holt, a subplot in "The Road Trip".
- "Wild Side" by Motley Crue plays during the squash tournament montage.