Based on a 2013 nonfiction book of the same name by Robert Kolker, the movie centers on Mari Gilbert, played by Amy Ryan, a single mother of three juggling multiple jobs whose daughter Shannan, an escort, goes missing after meeting with a client in the Oak Beach area of Long Island. During Mari’s search for Shannan, police discover the bodies of several women, most of whom are believed to be sex workers. Incensed at the way law enforcement ignores their cases, Mari take it upon herself to advocate for her daughter by joining the families of other missing and murdered sex workers and convincing police to investigate.

A heartbreaking story about one mother’s efforts to find answers about her child, and the community she builds along the way, Lost Girls is the narrative feature debut for director Liz Garbus.