The guest star had a “Mount Vesuvius of imagination,” said the Fonz.

Henry Winkler reveals Happy Days guest star he couldn’t go ‘toe to toe’ with: ‘Stay out of his way’

The guest star had a "Mount Vesuvius of imagination," said the Fonz.

By Daysia Tolentino

Daysia Tolentino

Daysia Tolentino is a writer at *. *She has written for * *since 2025. Her work has appeared in NBC News, Vulture, GQ, and InStyle.

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December 26, 2025 8:00 a.m. ET

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Henry Winkler as Fonzie on 'Happy Days'. Credit:

Gene Trindl/TV Guide/ABC/Courtesy Everett Collection

Even the Fonz knows that Robin Williams had a je ne sais quoi he couldn't compete with.

Henry Winkler recalled Williams' audition for Mork the Orkan on *Happy Days*. He shared that the *Good Will Hunting* actor seemed "unassuming" on first sight. Once the comedian got a script in his hand, Winkler saw the magic in the then up-and-coming Williams.

"All I thought about was, 'Know your lines so you don't have to do it over and over again and stay out of his way because you will never stand toe-to-toe with this Mount Vesuvius of an imagination,'" Winkler said during a Fan Expo San Francisco panel, which was captured by It's Rec Time Media on TikTok.

Robin Williams as Mork in 'Mork & Mindy'.

Courtesy Everett Collection

Williams rose to prominence as the quirky, comical alien Mork, first as a guest star on *Happy Days* and then as the protagonist of its spin-off *Mork & Mindy.* His show ran for four seasons between 1978 and 1982.

The *Barry *actor recalled the late comedian's improv skills. He said that *Mork & Mindy *scripts were half the size of *Happy Days* ones because writers would leave space for Williams to do his own thing.

"It said, 'Robin will say something here," Winkler recounted.

Penny Marshall, Robin Williams, Henry Winkler on 'Happy Days'.

Courtesy Everett Collection

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Williams died by suicide in 2014 at the age of 63. Shortly after his death, Winkler paid tribute to the *Dead Poets Society* star and his talents in an interview with *Today*. He similarly remarked on Williams' role as Mork and his colorful imagination.

"This man was from another plane," the Fonzie actor said at the time. "His imagination flew out of him, out of every pore like a torrent."

Original Article on Source

Source: “EW Comedy”