Paul Bettany Used to Hide from Bullies During Recess: 'I Was Shy' and 'Incredibly Skinny'

Paul Bettany has found success as a Marvel star, but years before he stepped into the role of Vision, the actor says he was once "the shyest boy on earth."

Bettany, 50, told PEOPLE on the set of his Sexiest Man Alive photoshoot that he was a bashful young man growing up in London. The WandaVision star says school was especially difficult for him, recalling that he never put his hand up in class and "couldn't talk to anybody."

"I used to hide in the deputy headmaster's office during, I guess what you call, recess, because I was very bullied, and I was just shy," Bettany says.

The actor says he was an "incredibly skinny" and "terrified" teen who "used to wear two pairs of jeans" to try and hide his thin frame.

"I was very awkward, and not just physically, I mean, I looked like a foal that had just been born that couldn't stand up properly," he says. "But also just socially, I was really inept."

While he went on to star in films like A Knight's Tale, A Beautiful Mind and Iron Man, Bettany didn't have big dreams of becoming an actor growing up. He tells PEOPLE, "I had aspirations to survive secondary school and that was about it."

After school, he set his sights on becoming a guitar player, but his shyness got in the way when he was too nervous to perform his songs.

"I ended up an actor through a very long, strange process," he says. "I hated singing my songs in front of people, which is obviously a stumbling block to being a singer/songwriter."

When he "fell into acting by a mistake," Bettany found it suited him much better, explaining, "What I really liked about it was there was a buffer between me and the audience."

Before enrolling in drama school, Bettany says he was "very, very, solo," but everything changed for him when he stumbled into acting and "sort of found [his] feet socially." Bettany comes from an acting family; his father, Thane, worked as an actor and teacher while his mom, Anne, taught drama.

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Bettany says he has since shed his self-consciousness, a transition that happened in his mid-to-late twenties when he "stopped feeling so much shame and embarrassment over everything."

He's learned to lean into the cringe-worthy moments, explaining, "The sooner ... something embarrassing or terrible happens to you, the sooner you can make it a funny story. It just all goes away."

Bettany adds, "I spent a lot of time stressing about things that never f------ happened."