It seemed to be an open and shut case of larceny. Get back the poor guy's stolen necklace, simple, right? Things turn out to be a bit more complicated when said guy is murdered a couple days later, and the necklace in question is sought after by some of the most dangerous crime families in the USA. The FBI appoints the Nine-Nine to track down this necklace and help take down the criminal organizations that are after it as well, leading them on a cross-country chase down. Also, a lot of Peraltiago because I mean come on.