An insightful, heart-tugging documentary, “Super/Man: The Christopher Reeve Story” honors a Hollywood luminary who first became famous playing Superman and then, when tragedy struck, became a real-life hero to millions.

Reeve died 19 years ago when he was just 52. Nine years earlier he had broken his spinal cord in an equestrian accident and would never walk again.  He became an advocate for the disabled, funded research that changed the prognosis for the paralyzed and showed the world exactly what true grit and an unbreakable spirit look like.

His children continue his advocacy. Will, 32, is an ABC News correspondent. We spoke with Matthew Reeve, 44, and his daughter Alexandra Reeve Givens, 40.

“It’s been so heartwarming to see the response, to see people connect and remember his story,” Givens said. “But also how many people are seeing themselves in the film. Because it explores these big themes about life after a transformational accident.

“It also shows what it is to be a partner with someone through thick and thin. What it is to navigate a complex relationship with your father. What it is to be a friend and show up for people.

“The part I don’t think I had expected (but has been really lovely to see) has been so many people coming up, wanting to share their own stories of when they’ve experienced similar moments.”

“One of the objectives was to introduce him to a whole generation of people who may not know him,” Matthew said. “Also, reintroduce him to people who did know him and show all sides of him. It’s been wonderful hearing how they didn’t know he could play the piano so well or he could fly an airplane” – Reeve did two solo flights over the Atlantic!

“It’s been gratifying, people just get a deeper sense of who he was and what he went through. Towards the end of the film, he started to see his life as one continuum, rather than two halves — Before and After the accident.

“For both of us, any time you see something from your parents’ lives before you were around is always interesting. So for me, the scenes of Juilliard when he’s doing those funky movement exercises with his drama class was really fun.”

Almost like destiny, Reeve went to London to screentest on his one day off from a play and won the role that would change his life.

“Revisiting that time period,” Alexandra said, “I’m just suddenly thinking with the perspective of what an unbelievable journey that would have been. To be a virtual unknown in an off-Broadway dressing room who’s suddenly on a rocket ship to stardom! When he was still in his early 20s.”

“Super/Man: The Christopher Reeve Story” opens Oct. 11

Matthew Reeve, left, Alexandra Reeve Givens and Will Reeve attend the premiere of “Super/Man: The Christopher Reeve Story” at the Museum of Modern Art last month in New York. (Photo by Evan Agostini/Invision/AP)