With hindsight it is easy to see a unifying theme of psychic turmoil in the late actor’s work. He turned his pain into our pleasure, Lisa Schwarzbaum writes.

The shock from the awful news that Robin Williams ended his own life on 11 August is still fresh. The fact is all the more discordant given the effervescent persona of the public performer: quicksilver comic, antic improviser, fountain of observational riffs, expressive actor, exuberant talk-show guest. Obituaries recounting Williams’ quick rise and hard-working career – from lovable alien on the popular late 1970s sitcom Mork and Mindy, through his Oscar-winning performance in 1997’s Good Will Hunting, to his striking 2011 Broadway debut in Bengal Tiger at the Baghdad Zoo – now alternate with sombre reportage on the seriousness and signs of clinical depression. Williams, in the words of his personal publicist, had been “battling severe depression”, and he himself had spoken freely about his ongoing struggles with the drug and alcohol addictions that are so often the demons that flay the souls of the depressed. Earlier this year, he had checked himself into a rehab facility.

It is dangerously easy for observers with no direct connection to the man (a huge population that includes me) to peer at Williams’ performances through a filter of psychoanalytic empathy: the sad clown, the tortured charmer, the self-hating dispenser of pleasure. But it is reasonable and a fitting acknowledgment of the late artist’s gifts to recognise and admire how intently he drew on his pain to make something to entertain others. In this he joins a fraternity of actors and, especially, comedians, who did some of their best work on a high wire between pain – and its close sibling, rage – and laughs. It’s a club that includes Williams’ comedy idol Jonathan Winters, as well as Lenny Bruce, John Belushi, Richard Pryor, Spike Milligan and Stephen Fry. Williams just invented his own mad formula.

That alchemy began with his rise to stardom as Mork from the planet Ork, the goofy alien he played for four seasons (1978-1982). Yes, the then 27-year-old son of an affluent Midwestern family was trained in drama at New York’s prestigious Juilliard School, where his classmates famously included Christopher Reeve and Kelsey Grammer.  But it was his arrival on TV in an egg-shaped space capsule, all alone and bewildered by this place called Earth, that brought the young actor fame.

At the same time, in stand-up comedy routines and on talk-show appearances, he honed his skill at lightning-quick improvisation, free-associative monologues and vocal impersonations. The way for a TV host or co-star to ‘talk’ to Williams was to proffer a line of questioning and then stand back while the fellow spun circles, alone. That he developed a less-than-sterling reputation among fellow comics as a joke stealer takes on a certain pathos under the circumstances, one that tempers the impropriety: such incessant circle-spinning perhaps required more fuel than one comic could generate on his own.

Meanwhile, as television and stand-up performances allowed him to let off psychic steam – dazzling creative gusts belched out by a nimble man running, always running, from the tangle inside himself – movies let Williams bare himself in ways so inventive that they became camouflage.

Emotional eruption

It is no accident, surely, that the extremities of his acting career were bordered by painfully schmaltzy characters at one end – consider, if you must, Patch Adams and Jakob the Liar – and creepy, alienated, sometimes evil lurkers at the other, including Insomnia, The Night Listener and One Hour Photo. In between, the star was forever drawn to characters at home with subterfuge (World’s Greatest Dad) or a taste for the maudlin (The Birdcage). The terrors and pleasures of fatherhood and, by extension, the yearnings a boy or young man might have for a good father or father figure, got a strong working out in projects as fine as Good Will Hunting and Dead Poet’s Society, and as imperfect as Father’s Day and, yes, World’s Greatest Dad. If, as some believe, there is no such thing as an accident, then surely there is a unity to the many plots of Williams’ movies in which family dysfunction serves as either a plot catalyst (as in the cringeworthy road comedy RV, in which married life is also seen in a withering light) or curdled diversion (as in August Rush, in which Williams plays a kind of benign Fagin to a gaggle of homeless children).

I put in its own category of cinematic parenthood, and self-redemption, the career highlight that is Mrs Doubtfire (1993). In one brazen and funny amalgam of light and dark, impersonation and sincerity, naughtiness and earnestness about parents, spouses, children and drag, Williams had all the pieces of his puzzle interlocked. And we the audience loved him for it. Of course, the massive bosom and silver wig helped a lot. The man was often most at ease within himself when disguised as someone or something else. It’s reasonable, now, to consider the relief a man battling melancholy might find in being, if only for a while, an android who could imitate emotions as in Bicentennial Man. And better yet, how wonderful to be a voice, just a gloriously funny voice, freed of one’s own frailty-prone body and given magical shape as Aladdin’s genie. Or a Rockhopper penguin in Happy Feet.

With a filmography so full, Robin Williams offered himself up with a unique desperation for the love that the audience readily gave him, but which we now know to our frustration and sorrow he could not always feel. He did work of wildly varying quality – some of the greatest stuff on screen and some of the worst, some of the funniest comedic intellectual gymnastics and some of the lamest. Now, as the world mourns the loss of a talented, tortured man, the sum of that work in all its variation takes on a different kind of sweetness. We now know more about the exhausting effort Williams expended in order to fight what felt like a personal abyss, until he could not fight any longer. That knowledge brings sadness, but also gratitude for the brilliance that erupted from him out of the darkness.

If you would like to comment on this story or anything else you have seen on BBC Culture, head over to our Facebook page or message us on Twitter.