Frontline (1983)

"League of Denial: The NFL's Concussion Crisis," October 8, 2013 This two-hour Frontline special, built on reporting by Mark Fainaru-Wada and Steve Fainaru, traces how brain damage was found in former Steelers center Mike Webster and how the league responded as evidence mounted that football harms players' brains. Its strength is structure: the first hour is detective work in the lab, the second a record of institutional resistance, with archive footage and long interviews doing the arguing. ESPN, originally a partner, withdrew weeks before broadcast, and the NFL declined to take part. PBS offers it to stream, which makes it the easiest starting point on this list for newcomers.