Transcript for 'Basketball: A Love Story': The game's legends explore its key moments in history
Reporter: A perfect swish. A gravity-defying dunk. Seemingly super human athletes. You know everything's in rhythm. Reporter: There's a reason it's called the beautiful game. It was like the Gates of heaven just opened up. Reporter: A game so beloved, it's like an addiction. In my family, we still call it basketball fever. It's like you have to play all the time. Reporter: From the driveway. I started playing on a crate, cut the bottom out, nailed it to the light pole. Reporter: To the hardwood. The squeak of the shoes and then that magic sound, swish. Reporter: Now, the subject of ESPN's epic 20-hour film series, "Basketball: A love story," featuring some of the biggest names in the game. My name is Lebron James. Kobe Bryant. Magic Johnson. Reporter: The film chronicles hoops for over half a century, tapping into pivotal pressure points like racial injustice. I felt like we was in a hostile situation. All the news reporters was fighting. Cheerleaders was fighting. The whole bench of the other team was all white. Only colored person I seen was on my side. Reporter: Basketball came of age during the civil rights movement. Early the pearl Monroe, a legendry New York knick is hall of famer is one of the producers of the film. What was that like for you at the time? I mean, I played in north Carolina in college, and there were places that you could go and places that you couldn't go. Well, that was just the times. Reporter: Soon, stars of the game like Kareem Abdul jabar started to advocate for social change. Kareem 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. Reporter: But given the platform, given the times, do you think they have a responsibility to step up and speak up? I think the main thing that a player should always do is just be a role model. You don't have to speak up. You just have to live the right way. Reporter: Unlike the NFL, which has been riled by its response to players kneeling for the anthem, the NBA has mostly been supportive of players' activism. They're much more in tune with the times, with the culture, with the politics of the day. They're not a bunch of billionaire owners from another sport sitting around with the same complexion say, hey, we got to stop this guy from kneeling. Reporter: From race to gender, the film exposes the rocky past to equality in the game. I learned very early on that basketball was very different for me. Because I was a girl. It was okay for me to score 20 but wasn't a man's 20. So I said, oh, so my 20's not good enough? All right, I'll score 105. Reporter: Women had to struggle for their place on the court. I wish there was somebody who looked like me. I wish there was a woman playing somewhere that was on TV every week and was showing little girls how to play hoops, but that wasn't life then. That wasn't life in the '70s, '80s and early part of the '90s. Reporter: The wnba was a big step forward, founded in 1996 after the U.S. Women's olympic team and a young Rebecca lobo won gold in Atlanta. It was so much bigger than that. We didn't realize we were a test bubble, essentially, for the wnba. Reporter: The birth of the first major women's professional sports league in the country was not without growing pains. We tried to conform the image of this league to what we thought the fans wanted. ?????? The first video shoot of the wnba, they had me, like, pull my hair down, lipstick. I had a Halter top on. I never felt so bad in my life. It was weird but we were just so happy that we had a place to play. We were willing to do pretty much anything. Reporter: Overall, the league opened doors to female ballers. The wnba is a success both in turnout and in TV ratings. Reporter: Our own was there to cover the inaugural season. In my wildest dreams, I couldn't have thought it would be this good. This was all new to us and not something any of us had thought about because it didn't exist when we were growing up. It would have been a pipe dream. Reporter: What has the wnba added to the growth and the love of the game of basketball? It's an experiment that has worked. You know, you got all these critics, oh, they don't play as well as men. They're not supposed to play -- it's a different game. Look what the wnba has meant to the culture, to young women, to girls. It's all about a host of other doors that are opening and have opened on every conceivable level that give to people what they need, pride, encouragement, hope, and confidence. Reporter: Those feelings intrinsic to the game itself. You stand in right center court in the garden now, man. What goes -- how you feel standing out here still to this day? It's a great feeling. Reporter: Back on the court he loves. His next Jersey, proudly hanging from the rafters. Reporter: A game of individuality, yet teamwork, greatness, yet equality. And most of all, a game of love. It's a story about basketball being a global common denominator. Reporter: For "Nightline," I'm T.J. Holmes in Madison square garden. Our thanks to T.J. And "Basketball: A love story" can be found on the ESPN app and the two final episodes air Tuesday night at 8:00 P.M. Next, news about an ABC news
This transcript has been automatically generated and may not be 100% accurate.