Just keep dreaming and going after your dreams. his story on his podcast in 2010. What were you doing there? A movie called the big white. Feeling isolated and all of a sudden went, well, there's one... See More
Just keep dreaming and going after your dreams. his story on his podcast in 2010. What were you doing there? A movie called the big white. Feeling isolated and all of a sudden went, well, there's one cure. Reporter: With a string of recent setbacks, things might have seemed more bleak, alcohol abuse ending his second marriage, his two divorce settlements cost him roughly $30 million. He recently put his napa ranch on the market, saying he couldn't afford it. And his new sitcom, "The crazy ones" cancelled after one season. But he almost always bounced back. In the beginning success came quickly. His talent bringing him to the famed juilliard school. He forged a lifelong friendship with friend, Christopher reeve. Marshall said he hired Williams on the spot, saying he had never interviewed an alien before. He did the audition standing on his head and did a bunch of strange alien things and he got the part. Reporter: On that moment on happy days when the fonz opened that front door. Whoa, whoa, whoa! Reporter: Actor Henry Winkler telling me tonight he will never forget it. When he shows up at the Cunningham house and you open the door, it was almost like a metaphor of robin Williams bursting onto the scene. You knew when you first watched him from the very first minute he picked up the script and started to improvise that you were in the presence of someone who was phenomenal. Reporter: That character such a hit, producers creating a spinoff, "Mork and Mindy." At one point more than 60 million viewers tuning in every week. Hello, anybody in there? Reporter: Williams would transition to the big screen, starring in a string of films, among them, "Good morning Vietnam." I'll get you my pretty. It's the wicked witch of the north. Reporter: And the world would soon see his more serious side, taking on the role of John Keating, the unorthodox English professor in dead poets society who challenged and shaped young minds. Words and ideas can change the word. Reporter: Williams would change the world, too, joining fellow comedians whoopi Goldberg and Billy crystal to help the homeless. You'll feel good, we'll feel good. I feel good. Reporter: Williams also championed the U.S.O., celebrating our troops all over the world. Good morning, Virginia! Reporter: The bob hope of his generation, he entertained nearly 90,000 troops but it was his turn as a psychologist that would finally earn robin Williams an Oscar. Robin Williams in "Good will huntin hunting". This might be the one time I'm speechless. Thank you so much. All the generations coming together at the family dinner and everyone at that table will have a favorite movie and it's likely different from the person across from him. After he died there were a lot of posts on Facebook and instagram of people posting their favorite movies and different generations post different things. I would have probably posted "Mork and Mindy" or "Mrs. Doubtfire." Another generation would have posted "Aladdin." Reporter: The animated classic "Aladdin" reaching a new generation of fans, animation, no match for. . He was discovered over and over again but he kept reinventing himself and he kept getting and doing incredibly good work through all of those years. Reporter: It's Williams' newest generation of fans who have overwhelmed social media with images, tributes of their own, many standing on desks tweeting o'captain my captain, a reference to that professor in dead poets society who touched so many. Sit down, Mr. Anderson. Reporter: Tonight there are so many questions over robin Williams' projects, so many of them well under way. He had a number of movies in the works. We know he was going to reprise his role in "Mrs. Doubtfire" among them. What happens now? I think "Mrs. Doubtfire" cannot happen without him. I think that one is going to be off the table. That role is so iconically robin Williams that you just -- you couldn't even think about making that movie. Hello! Reporter: A movie about a man willing to do anything to be with his kids, and in real life, robin Williams' last tweet was a picture of him holding his daughter Zelda Rae as a baby. His daughter tweeting overnight, I miss you, I love you, I'll try to keep looking up. This is a family, these are children left without their dad. What it says to me is just how much pain he must have been in when he died because, you know, you know what your family is going to go through, and I think he just could not find a way out of it.
This transcript has been automatically generated and may not be 100% accurate.