In 2013, a Florida jury finds neighborhood watchman George Zimmerman not guilty in the shooting death of seventeen-year-old Trayvon Martin, and the acquittal sets off a hashtag, #BlackLivesMatter, that grows into one of the largest grassroots movements in the United States. VPRO Backlight sits down with Patrisse Cullors, one of the movement's three co-founders, who lays out the forms of violence, physical, economic, institutional, that made the movement feel necessary rather than optional. The film moves beyond the Trayvon Martin case into the broader pattern of police killings of black citizens that kept the hashtag active, and into the organizing work of building a decentralized network out of local chapters and social media. Cullors talks through what resistance looks like on the ground: marches, mutual aid, political pressure, and the exhausting work of keeping a leaderless movement coherent. Filmed in 2016, three years into the movement's life, it captures Black Lives Matter as an ongoing organizing project rather than a finished story.