Robin Williams was a performer with breathtaking range. He coulding hilariously unhinged, also heartbreakingly tender, sometimes in the same scene. Tonight we take a look back at some of his most... See More
Robin Williams was a performer with breathtaking range. He coulding hilariously unhinged, also heartbreakingly tender, sometimes in the same scene. Tonight we take a look back at some of his most unforgettable moments and hear Williams' own thoughts on the craft he mastered. Here's ABC's David Wright. We did it. ? I'm driving in my car ? ? turn on the radio ? Reporter: As a comedian and actor robin Williams always seemed slightly possessed. People think of method actors going, what's he saying? Shut up, he feels it. Reporter: His pace, frantic. His energy super charged. Look, five yards, let's go! Don't you know, listen now. Master! I don't think you quite realize what you've got here! Why don't you just rule mate while I illuminate the possibilities? Reporter: The perfect choice to voice the genie from Disney's "Aladdin." Hollywood often struggled to find a bottle big enough for his genius. Nano-nano. Reporter: Williams was already in his late 20s by the time ABC's "Mork and Mindy" made him a star. His character, Mork from Ork, spun off from one of the latter episodes of "Happy days," a dream sequence where the good-natured space alien tries to abduct Ritchie Cunningham only to be foiled by the fonz. So do men date women on your planet? Hard to tell, parts are interchangeable. Reporter: Williams was so out of this world, ABC gave him a sitcom of his own. Mork, will you help me? If you insist. Mindfy cut in? Thank you. Reporter: A comic genius who had trained at julliard to be a serious actor. Shakespeare, exciting to wear tights and have people go, I can't see anything. Someone give him a dagger! Reporter: The big screen was better able to capture a personality his size. Among his first roles, one of the most iconic cartoon heroes. I'm popeye. The sailor. Reporter: Williams came into his own when he started playing offbeat heroes with a strong streak of humanity. Garp in "The world according to gap." My name is T.S. Garp. What's T.S. Stand for? Terribly sexy. I used to be terribly shy but I changed. Seize the day. Gather while ye may. Why does the writer use these lines? Because he's in a hurry. No, beep. Thanks for playing anyway. Because we are food for worms, lads. Because believe it or not, each and every one of us in this room is one day going to stop breathing, turn cold, and die. Reporter: The loveable teacher in "Dead poet society." Seize the day, boys! Reporter: Almost a button-down, collar prep school version of his standup style. Why do I stand up here, anybody? To feel taller. No. Thank you for playing, Mr. Dalton. Good morning Vietnam! Reporter: And as the crazy wartime deejay Adrian Cronauer in "Good morning Vietnam." His forceful personality allowing him to tackle issue. The Buffalo, there's horns everywhere, I think we're going to have a little napalm there, have a little barbecue. Reporter: In "The bird cage" a flamboyantly gay father. In "Mrs. Doubtfire," a cross-dressing Mary poppins. Hello! Reporter: At the time, Williams' own marriage had recently fallen apart. I want a divorce. Reporter: Scenes like this must have resonated from his own personal life. It was his portrayal of a south Boston psychiatrist that won him his Oscar. This girl's Perfect right now. I don't want to ruin that. Maybe you're perfect right now, maybe you don't want to ruin that. But I think that's a super philosophy. That way you can go through your entire life without having to ever know anybody. Reporter: In "Good will hunt" counseling a complex and hugely talented kid. You don't know about real loss. Because it only occurs when you love something more than you love yourself. I doubt you've ever dared to love anybody that much. Reporter: As the wild-eyed hero of a board game brought to life in "Jumanji." You'd hardly think of robin Williams as presidential, would you? Yet he played two commanders in chief. 26th president of these United States of America at your service. Reporter: The rough rider teddy Roosevelt in "Night at the museum." Not much of a stretch. Excuse me to you. The hunt. Reporter: Then more recently in "The butler," robin Williams played Ike. In some ways the ultimate, the iconic commander in chief. Williams later told James Lipton on "Inside the actors studio" that he loved transforming into character. You start to do these things where you really start to make a character, someone who isn't yourself, someone combined with makeup, movement, all these different things. You really start to get outside yourself and you're freed to be behind, operating it. That was a really fascinating thing for me. Reporter: He always brought part of himself too. His humanity. Struggling to contain all those characters bursting to get out. This is Mork signing off. Till next week. Reporter: I'm David Wright for "Nightline" in Hollywood. I remember watching that show every week as a 7-year-old. Coming up on "Nightline," a
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