What do Tom Cruise, Hosni Mubarak, and neo-Nazi radio host Hal Turner have in common? They’ve all felt the wrath of Anonymous, that diffuse, much-publicized group of hacktivists with a penchant for anarchy, government accountability, and plastic Guy Fawkes masks. Director Brian Knappenberger peers behind the masks (a surprising number of “Anons” appear in the film bare-faced and using their own names) in the impressively thorough We Are Legion, which follows the group’s fascinatingly rapid development from a crackpot, 4chan-centered meme factory to—thanks to its involvement in the Occupy Wall Street movement and its delivery of “digital care packages” during the Arab Spring—an increasingly visible political force. It’s a glowing portrait, and anyone looking for a critique of some of Anonymous’ more problematic attributes—its lack of a clear political agenda, its penchant for antagonistic trolling—will find the film one-sided. Still, its detail makes We Are Legion a vital study of what it means to be an activist in a digitizing world. —LZ