Justin Long "became an actor" because of Michael J. Fox.
The 45-year-old star has revealed that he's been inspired by the 'Back to the Future' actor, describing Michael as a "brilliant" man.
Justin told PEOPLE: "His humour and timing. And his comedy is, he's just brilliant. He really is the reason I became an actor."
Michael was diagnosed with Parkinson's disease in 1991, when he was at the height of his fame and success. And although the Hollywood star has subsequently reduced his acting work, Justin remains full of admiration for him.
Justin said: "I so admired him growing up, and I admire him exponentially now as a man."
Earlier this year, meanwhile, Michael admitted that his meteoric rise "made no sense" to him.
The actor - who moved from Canada to the US at the age of 18 - initially struggled to find work in Hollywood, but he shot to international stardom as Marty McFly in the 'Back to the Future' franchise.
Michael - who also starred alongside his now-wife Tracy Pollan on the NBC sitcom 'Family Ties' - told 'Entertainment Tonight': "I was dumpster diving because I knew the grocery store would throw baked goods out. We'd steal jam and peanut butter from the IHOP or Denny's. It was a tough existence.
"But in a relatively short period of time I was famous and I was the biggest movie star in the world ... It was crazy. It made no sense."
Michael regards his marriage as the "best 35 years of [his] life".
He explained: "We give each other space to make mistakes. Always remember that. Don't perceive slights ... That's what's beautiful about marriage, it's us two."