Known for his preternatural performance agility, lightning-fast impressions and malleable voice, Robin Williams was a versatile actor beloved by several generations.
Fun-loving as he seemed, he also was a deeply disciplined actor ever in search of challenge and complicated roles.
Those fans and the Hollywood community were in mourning Monday after the Oscar-winning actor/comic was found dead in his Northern California home, a possible suicide, according to investigators. He was 63.
Baby boomers first became acquainted with him in 1978 as Mork, TV's lovable clownish alien in rainbow-colored suspenders on the Mork & Mindy sitcom.
Williams started out doing improvisational stand-up comedy in the late '70, and those witty reflexes, honed early, made him singular in his comic brilliance. Yet it was his prodigious intelligence, ferocious intensity and charismatic, maniacal and razor-sharp wit — which sometimes seemed to tread on the edge of sanity — that allowed him to reach into the heart of a character in his varied and impressive dramatic roles.
His breakout role in film, an edgy Vietnam War-era DJ in 1987's Good Morning, Vietnam, confirmed his massive likability and spot-on comic timing.
His appeal was one of the broadest among contemporary Hollywood actors. He could play an earnest English professor in Dead Poets Society and a benevolent nanny in Mrs. Doubtfire with equal aplomb. As the quick-witted genie in Aladdin, he easily stole the 1992 movie and won the hearts of the youngest audience members.
He was one of the rare actors who was able to transcend his comic origins and be taken seriously as a dramatic actor. Indeed, he was widely admired in Hollywood, receiving the ultimate honor from his peers, an Oscar for best supporting actor in 1997's Good Will Hunting.
He excelled at playing energetic teachers, the kind we wish we'd had in school, but he was equally adept at playing characters on the edge of lunacy, such as the homeless philosopher in The Fisher King.
Among his 70 movies, he made some bad choices in material. Patch Adams, Popeye and Hook were clunkers, but Williams was indefatigable, always striving for singularly intriguing performances.
He worked with some of the industry's most challenging and artistic directors, including Terry Gilliam, Robert Altman and Woody Allen, while still taking roles in more predictable blockbusters that are actors' bread and butter.
Some of his best performances were his darkest roles. His disturbing portrayal of an obsessed loner in 2002's One Hour Photo was eerie and indelible, and that same year he starred as a villainous crime novelist in the taut thriller Insomnia.
His loony-jolly characters were fan favorites, however, perhaps because they were inspired by similarly offbeat comedians. Among those he admired most: Jonathan Winters, Charlie Chaplin, Jackie Gleason and Bill Cosby.
"You're only given a little spark of madness, you mustn't lose it,'' he once said.
When he hit his late 50s and early 60s, Williams had deftly played presidents, most recently Dwight D. Eisenhower in 2013's The Butler and also Teddy Roosevelt in the Night at the Museum movies.
In the last decade, Williams seemed drawn to even more offbeat and provocative roles. Ironically for a man who could easily make audiences laugh hysterically, his serious, darker characters might have left the most indelible impression of all.