Will Lyman

~ as ~

Himself - Narrator

Harry Carson

~ as ~

Himself

Steve Fainaru

~ as ~

Himself

Mikey Collins

~ as ~

Himself - University of Pittsburgh Medical Center

Bennett Omalu

~ as ~

Himself - Medical Examiner

Ann McKee

~ as ~

Herself - Neuropathologist, BU CTE Center

Stan Savran

~ as ~

Himself - Pittsburgh Sports Reporter

Julian Bailes

~ as ~

Himself - Team Physician, Steelers, 1988-97

Jim Otto

~ as ~

Himself

Mike Webster

~ as ~

Himself (archive footage)