New parents Mac (Seth Rogen) and Kelly (Rose Byrne) move to the suburbs when they welcome an infant daughter into their lives. All goes well with the couple, until the Delta Psi Beta fraternity moves in next door. Mac and Kelly don't want to seem uncool, and they try their best to get along with frat president Teddy (Zac Efron) and the rest of the guys. However, when the couple finally call the cops during a particularly raucous frat party, a full-scale war erupts.