Seth Rogen and Rose Byrne are back as Mac and Kelly Radner, a congenial but ditzy couple who worry they're losing their hip cred as they grow into parenthood. They also worry that they aren't actually growing into parenthood, and that they're making mistakes with their dildo-addict daughter Stella (played by Elise and Zoey Vargas, the same cute twins from the first movie). When 18-year-old Shelby (Chloë Grace Moretz) and her best friends Beth (Kiersey Clemons) and Nora (Beanie Feldstein) launch a new sorority in the empty former frat house next door, Mac and Kelly react shrilly enough to justify their concerns over their maturity level. Just as they went to war with frat leaders Teddy (Zac Efron) and Pete (Dave Franco) in the first film, in the sequel they reenlist their friends Jimmy (Ike Barinholtz) and Paula (Carla Gallo) to sabotage Shelby and her sisters. Events escalate quickly.

Who knew gross-out comedy could be politically progressive?

As with the first Neighbors, Stoller and the other writers take the time to establish both sides of the conflict, and dig into the concerns that make Shelby and her sorority sisters more than faceless foils. The film's clear sympathy for Shelby's crowd and their budding feminist defiance isn't subtle, but it's even-handed and startlingly progressive. As Shelby points out early in the film, the National Panhellenic Conference, which governs sororities, prohibits them from drinking alcohol in their own houses, so only fraternities can throw parties. (This is a real thing: "Google it," Shelby snaps, mostly to the audience.) By starting her own unlicensed, ungoverned sorority, she's trying to dodge the rules, dodge skeevy frat parties, and stand up for women's freedom to get drunk, high, and laid on their own terms.

But there's no such thing as a legal right to party, as Pete wearily explains once Teddy starts coaching the sorority in an attempt to relive his happy frat years. Shelby's cause is petty and self-absorbed, and a more judgmental film would use that to mock the feminism she uses to clothe her actions. Neighbors 2 toys with some dangerous themes by having her and her friends use their youth and sexuality as a weapon, particularly against Mac, who's openly terrified by the skin they flash at him. But the film also accepts Shelby's frustrations as real to her, appropriate to her youth and inexperience, and relevant to real-world sexism. It takes her small ambitions of sisterhood as seriously as it takes anything in its story, even when she expresses those ambitions childishly. The film is broad enough to integrate its female-empowerment message into the overall air of amiable anarchy, instead of turning it into shrill moralizing. (Still, in all the hoopla over Paul Feig's female-led Ghostbusters, where's the frothing, self-righteous outrage over Neighbors 2, which also replaces the men in an popular comedy with ladies, then builds an entire theme around women's equality?)