From rocky start to Oscar hopeful: Dwayne Johnson hits Toronto

- Transformation -

The former grappler and action hero has never lacked bulk. But when Johnson signed up to play Kerr, director Benny Safdie had an unusual request.

"Benny, early, said, 'I don't know if you've ever been told this before, but I think you're gonna need to gain weight,'" recalled Johnson.

Johnson hit the gym for a few months, gaining 30 pounds (13.6 kilograms) of muscle to emulate Kerr's even-more-gargantuan physique.

The role required three to four hours of facial prosthetics every morning before filming.

And to mimic Kerr's soft speech, Johnson employed a voice coach for the first time in his career -- hiring the teacher used by co-star Emily Blunt for "Oppenheimer."

- Canadian homecoming -

Before "The Rock" entered a wrestling ring, Johnson had another career -- pro football.

"I played for the Calgary Stampeders" in Canada's gridiron league, he recalled, to cheers from the Toronto audience.

"I always thought I was going to be an NFL player. I was going to take care of my parents, buy them their first home," said Johnson.

Instead, Johnson never made the team, and returned to the United States after being cut.

It mirrored his father's own journey. Rocky Johnson had spent years in Toronto, living homeless at age 13, before becoming a successful wrestler himself.

- Rocky start -

At first, wrestling didn't come easy to the younger Johnson either.

He recalled shouts of "You suck!" from spectators early on, until he knuckled down and learnt his father's trade.

It is a lesson Johnson took to Hollywood, when he was cast in his late twenties in the lead role of "The Mummy" franchise spin-off "The Scorpion King."

"It was a baptism by fire," he said, recalling being "super nervous" and determined to absorb every lesson like "a sponge."

"It was like, here's your first film, here's your starring role... don't ruin it!"

Wild success followed with franchises like "Moana," "Jumanji" and "The Fast and the Furious" making Johnson Hollywood's top-paid actor.

But "I was pigeonholed because I allowed it to happen," recalled Johnson.

- Action to arthouse -

That changed when he met Safdie, who gambled that Johnson could take the plunge into arthouse film.

Johnson also credited Blunt -- an Oscar nominee, who told the panel the former wrestler was nothing like his persona.

"'The Rock' is the performance of a lifetime," said Blunt.

Safdie won best director at the Venice film festival for his work with Johnson -- and the pair are reteaming already, with "Lizard Music."

Based off a Daniel Pinkwater novel, the movie casts Johnson as an eccentric 70-year-old man whose best friend is a geriatric chicken.

"Benny pitched me this after we wrapped the 'Smashing Machine'," said Johnson.

"After about 45 minutes his pitch ended, and I said, 'I am your Chicken Man.'"

Worried that Johnson might be leaving his blockbuster roots behind entirely? There was some good news.

"We are going to start shooting 'Jumanji 3' in November," he said.

amz/mlm