Henry Winkler recalls struggling with Happy Days lines because of his dyslexia: 'I was so f---ing angry'

Fonzie might have been too cool for school, but Henry Winkler did not have the same relaxed attitude at the height of his sitcom fame.

The 77-year-old veteran actor has recounted his struggles while reading his lines on the set of the hit 1970s sitcom Happy Days because of his dyslexia, revealing that it led to feelings of deep insecurity.

In an excerpt from his upcoming memoir, Being Henry: The Fonz... and Beyond, Winkler writes that he was "so f---ing angry" when he learned about his diagnosis at age 31, several years into his performance as resident bad boy Arthur "Fonzie" Fonzarelli.

"Even in the midst of Happy Days, at the height of my fame and success, I felt embarrassed, inadequate," Winkler writes in an excerpt published by PEOPLE. "Every Monday at 10 o'clock, we would have a table reading of that week's script, and at every reading I would lose my place, or stumble. I would leave a word out, a line out. I was constantly failing to give the right cue line, which would then screw up the joke for the person doing the scene with me. Or I would be staring at a word, like 'invincible,' and have no idea on earth how to pronounce it or even sound it out."

Winkler continues, "My brain and I were in different zip codes. Meanwhile, the other actors would be waiting, staring at me: It was humiliating and shameful. Everybody in the cast was warm and supportive, but I constantly felt I was letting them down. I had to ask for my scripts really early, so I could read them over and over again — which put extra pressure on the writers, who were already under the gun every week, having to get 24 scripts ready in rapid succession. All this at the height of my fame and success, as I was playing the coolest guy in the world."

When Winkler was diagnosed, "I was so f---ing angry," he writes. "All the misery I'd gone through had been for nothing. All the yelling, all the humiliation, all the screaming arguments in my house as I was growing up — for nothing… It was genetic! It wasn't a way I decided to be! And then I went from feeling this massive anger to fighting through it."

The Barry star previously explained that he learned about his disability after his stepson was tested and evaluated for dyslexia. "I went, 'Oh my goodness, that's me,'" Winkler recalled to NPR in 2019. "And so at 31, I found out I wasn't stupid, that I wasn't lazy — that I had something with a name."

Winkler has since written several best-selling books, including the Here's Hank children's series, to educate others about dyslexia. "What I have found over the years talking to kids today about it is that our journeys are similar," he said. "The feeling of inadequacy, of embarrassment, of, 'Oh my gosh, am I going to have a future?'"

Being Henry: The Fonz... and Beyond is out Oct. 31.

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