Will Lyman

Himself - Narrator

Harry Carson

Himself

Steve Fainaru

Himself

Mikey Collins

Himself - University of Pittsburgh Medical Center

Bennett Omalu

Himself - Medical Examiner

Ann McKee

Herself - Neuropathologist, BU CTE Center

Stan Savran

Himself - Pittsburgh Sports Reporter

Julian Bailes

Himself - Team Physician, Steelers, 1988-97

Jim Otto

Himself

Mike Webster

Himself (archive footage)