In 2012, two young activists from the National Immigrant Youth Alliance went on an undercover mission to infiltrate the Broward Transitional Center, an Immigration and Customs Enforcement facility in Florida. NIYA had been contacted by the son of a man named Claudio Rojas, who was taken from his home by immigration agents and brought to Broward. NIYA has been compared to ACT UP; its members try to force confrontations with authorities over immigration policy. The two activists, who are themselves undocumented, pretended to be newly arrived, confused immigrants who spoke little English. They got themselves arrested by somewhat perplexed Border Patrol agents.

The story of those activists is told in a new film called “The Infiltrators,” which recently showed at the Sundance Festival and South by Southwest. It is a kind of quasi-documentary, the directors Cristina Ibarra and Alex Rivera tell David Remnick; because they were not able to film inside the ICE facility, they staged a reënactment of the events inside a decommissioned mental hospital. Rojas, who had been released from detention after staging a hunger strike, advised the production for verisimilitude. But after the movie’s release, Rojas was suddenly re-detained during a routine check-in with ICE, which he attended with his lawyer. “For eight years I presented myself for supervision visits,” Rojas tells The New Yorker’s Camila Osorio, speaking on the phone from detention. “Why didn’t they detain me before? . . . I am completely sure that this is a reprisal against me, that they want to deport me no matter what.”