Jake and Rosa investigate a case in which they have to assist InterPol. Amy and Terry team up to help Gina study for an exam, while Captain Holt recruits Charles to double with him in a squash tournament.
Jake and Rosa have to work on a diamond theft case with two colleagues from Sweden, but the closeness of the other team puts their own friendship on trial. Meanwhile, Charles is trying not to "unleash the beast" during a squash tournament with Captain Holt while at the precinct Terry and Amy help Gina study for an astronomy test.
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.