Opening with The Invisible War, a majordocumentary that engaged the public and policymakers in the United States, this chapter argues that contemporary documentaries play a unique role in public policy due to their narrative approaches—human-centered narratives that expand beyond facts and statistics and ideological sides—and the collaborative, cultural nature of the policymaking process. Documentary films can also expose social problems relegated to obscurity, or new on the cultural horizon—documentary’s monitorial function. This chapter delves into the complexities of documentary films that successfully shaped US laws through filmmakers working with legislators, policy experts, and issue advocates, forming “policy subnetworks.” The film case studies here include Sin by Silence, which changed California state law focused on incarcerated survivors of domestic violence; Semper Fi, the environmental justice story that sparked a new federal law; and Playground, an investigation of child sex trafficking in the United States that helped to shape federal and state-based laws.