In the 1960s, young George Carlin cuts his teeth in comedy - but stifles his rebellious instincts to achieve mainstream success. As the counterculture emerges, Carlin reinvents himself, shocking and delighting 1970s audiences.

After a slump in the '80s, Carlin comes back with a vengeance, reaching new heights - and new audiences - with another reinvention that highlights his prescient political commentary. Following his death in 2008, fellow comics reflect on his enduring legacy.