The joke on Robin Williams's Mork & Mindy — one of them, anyway — was that Orkan babies were born fully grown. And so when the time came, Williams and his TV spouse, actress Pam Dawber, then both 30, produced the middle-aged Jonathan Winters.

Williams, who died Monday at age 63, was a lot like Mearth, Winters's character. As a performer and comic force, he was born fully grown.

[Related: Live From New York, It's Robin Williams: 6 of His 'SNL' Highlights]

The best evidence of this is the above YouTube gem: an appearance by Williams on what's billed as an HBO comedy show, probably On Location (1977) hosted by David Steinberg.

The segment looks to have been filmed at the Improv in Hollywood. (The brick wall backdrop is the first hint.) Steinberg, the comedian and director (not the personal manager of the same name who would go on to guide Williams's career for decades), introduces Williams as a recent Los Angeles transplant by way of San Francisco. The club-goers clap politely. The 25- or 26-year-old Williams takes the stage, opens his mouth, and in that instant, becomes the Williams the larger audience would come to know him as.

He starts off affecting a Russian accent — just as he'd do in one of his early films, Moscow on the Hudson, and as he'd do again and again over the years, from concert stages to American Idol.

[Related: Remembering Robin Williams's Best TV Moments]

When, just a few seconds into the act, Williams drops his first non sequitur ("F--- a duck!"), he raises his arms, and you catch a glimpse of his rainbow suspenders — not unlike the ones he wore to his audition for the producers of Happy Days and not unlike the ones he made fashionable on the TV show that the producers of Happy Days would create for him, Mork & Mindy.

The rest of the set plays like a 10-minute trailer of Williams's career; nearly every trope, nearly every tic that you will associate with him is here. The nonstop banter. The nonstop riffing. The many, many, many voices, from his go-to Russian to a baby-voiced Southerner to a blowhard evangelist. (It's not for nothing Winters was cast as Williams's son on Mork & Mindy; Williams idolized Winters, who himself was known for switching on and off characters as deftly as light switches.) The references to the drugs and alcohol that Williams battled and joked about. The classically trained actor who occasionally emerges from the comic's suspenders.

[Related: Robin Williams's 19 Most Memorable Movie Roles]

Before the TV fame, before the movies and the Oscar, Robin Williams is Robin Williams. Just as he always will be.