Writer/director Siân Heder’s Being Heumann (A) delivers the absolute joy of seeing the too-often-invisible disability community brought to vibrant, exuberant life. Ruth Madeley is a sensation as Judith Heumann, the formidable Brooklynite badass disability-rights activist who helped lead the longest occupation of a federal building in American history back in the ‘70s. Heder honors the importance of that protest without reducing its participants to symbols, making room for partying, sexuality, laughter, liberation and the gloriously messy business of being human. Andrew Pilkington is a standout as Hale Zukas, who spells out his words one letter at a time but repeatedly lands some of the film’s funniest and most unexpected turns of phrase. Roberta Colindrez is equally memorable, bringing warmth and a crackling vitality to the ensemble. Familiar faces Mark Ruffalo and Dylan O’Brien also do fine work as a bract and reporter, respectively, while leaving the film’s disabled actors and their characters at its center. The result is both a rousing account of a movement that changed America and an irresistible celebration of the people who refused to remain unseen. The pace loses a touch of momentum toward the final act with a few plot threads getting short shrift, but oh the thrill of ultimate victories. Heder and her collaborators don’t merely reclaim an essential chapter of history; they throw open the doors and invite everyone to a party that still requires a bevy of believers.