. >> reporter: soon, stars of the game like kareem abdul jabar started to advocate for social change. abdul jabar says i'm going to boycott, i don't want to go to the olympics in '68. >> if you live in a racist society, you naturally have to react to racism if you are attacked. you naturally give a reaction. >> these guys are saying, i'm not going to play for the u.s. because of racism. that's a momentous thing. >> reporter: athletes today are following in abdul jabar's footsteps, protesting police brutality in the wake of eric garner's death. and after president trump relentlessly criticized nfl players for kneeling during the national anthem, rivals steph curry and lebron james backed each other up, refusing to visit the white house. >> i mean, i know no matter who wins this series, no one's -- no one wants to invite anybody. so it won't be golden state or cleveland going. >> i agree with bron. >> reporter: dan is the director of the film. >> people have the right to say what they want and it's great that people are speaking up. there's nothing wrong with that. it's tremendous. >> r