Robin Williams was one of the most original, daring and troubled comedians to ever work in television. When he first burst on the screen, you held your breath as you watched him dance out there on a manic tightrope of improvisation. But after a while, you stopped wondering how he did it and learned to just enjoy the high of seeing him soar.

The 63-year-old comedian and actor was found dead Monday at his home in Tiburon, Calif., north of San Francisco. The cause of death is suspected to be suicide by asphyxiation, according to the Marin County coroner’s office. But the cause is still being investigated.

Despite his Oscar-winning work in feature films, Williams will to a large extent be remembered in terms of his work on television. He started in the 1970s sitcom “Mork & Mindy” and he was a still a weekly prime-time presence on CBS in “The Crazy Ones” this year.

His late-night TV appearances are a treasure that will be savored for years, while his HBO concerts are landmark in the world of comedy and premium cable. One of his finest dramatic performances was delivered on TV in 1994 in the Baltimore-made series “Homicide: Life on the Street,” in which he played the husband of a young tourist from Iowa who is killed in front of him and their children while visiting Baltimore.

Artistically, Williams was light years better than network TV was in the 1970s. But instead of denouncing it and doing only comedy concerts and movies, he took one of its oldest genres, the sitcom, and bent it to his will, using it as a springboard to pop-culture stardom. He transformed the silliest of sitcoms into a dazzling weekly showcase of jaw-dropping improvisation and lightning-quick verbal dexterity worthy of his idol, Jonathan Winters.

Thanks to Williams, “Mork & Mindy” became one of the only sitcoms of that era that an adult viewer didn't have to apologize for watching — or talking about the morning after. With his manic energy and stream-of-consciousness pop-culture references, Williams managed to make the ABC series every bit as cerebral a viewing experience as watching “Saturday Night Live.” And most of Mork’s best lines were not in the scripts.

Mork arrived on Planet Earth and ABC as an alien from the Planet Ork who comes to kidnap RichieÖ Cunningham (Ron Howard ) in a 1978 episode of the ABC sitcom “Happy Days.” That’s what I mean by sitcom silly. That and Mork’s catchphrase: “Na-noo, na-noo.” The networks thought every sitcom had to have a catchphrase back then.

But the young stand-up comedian lit up the screen in the guest appearance with such physical zaniness that he was given a series his own series for the 1978-'79 season on ABC.

The premise here: He was cast off from Ork for his inability to get along with the powers that be. He landed in Boulder, Colo., in a giant egg and wound up living in the attic of a young woman, Mindy McConnell.

Mindy was sweet and square; Mork was snarky and hip — very, very, very hip. Sometimes, he sounded more like Lenny Bruce that the alien in a mime outfit. She helped him learn the culture here; he helped her learn, well, cosmic craziness and maybe wisdom.

I knew about Willliams before he appeared in “Mork,” and I got to write about him as TV critic. Because my wife was writing film scripts with a stand-up comedian from Los Angeles, we were given a backstage look at the world of California comedy clubs in that era — a world of dreams, drugs, nerves, nightmares, sex in lavatory stalls and daredevil acts of onstage invention.

Williams was a legend among California comedians back then — the smartest, fastest and most erudite, but also sometimes the most drugged and dangerous to himself.

Williams went on to do outstanding work in film. He won a Best Supporting Oscar for “Good Will Hunting” in 1997. He worked with Baltimore native Barry Levinson in “Good Morning Vietnam” (1987), “Toys” (1992) and “Man of the Year” (2006).

Levinson was one of the executive producers of “Homicide” when Williams appeared — a time when the series was under some pressure to increase its ratings. Williams’ presence helped it do just that.

Robin Williams didn’t do a ton of work in television. But he made the medium better with the work that he did do — like that appearance on “Homicide,” for which he earned an Emmy nomination.

He was the kind of fearless performer who made you feel privileged to write about his work.

david.zurawik@baltsun.com

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