Ben Affleck has been "starstruck" by Christopher Lloyd.
The Oscar-winning star - who is one of the best-paid actors in Hollywood - has revealed that he found meeting his 'Tender Bar' co-star to be a "very intimidating" experience.
Ben - who plays Charlie Moehringer in the coming-of-age drama film - told E! News' Daily Pop: "He's Doc from 'Back to the Future'!
"He showed up to the table read and I had that pang of being starstruck, of seeing this guy emerge from off the screen. Particularly the movies you see as a young person can make such a big impression on you."
Asked where his level of fandom would rank, Ben replied: "I tried to ask him for his autograph, but I couldn't get the courage."
Ben, 49, also relished the experience of working with George Clooney, who directed the movie.
He shared: "I love George. He's smart, he's funny, he's a great storyteller. He's fun to be around. He gets it. He's enormously charming and appealing, and it's because of his compassion and the amount that he cares about people and life and what happens in the world."
Ben likened working with George, 60, to playing on a basketball team alongside LeBron James.
He said: "It's like playing on a basketball team with LeBron. It's a gift."
Ben then jokingly added: "I told George I'm trying to negotiate a rate for him to come be my acting coach on my movies, but I can't afford him."
Meanwhile, a source previously revealed that Ben and Jennifer Lopez "plan on spending the holidays together".
The celebrity duo rekindled their romance earlier in 2021 and although they both have busy work schedules, they've made plans to spend time together over Christmas.
The source said: "They will both get a break. For Jennifer, Christmas is all about the kids. She makes it very special for them. She loves Christmas."
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