EXCLUSIVE: Michelle Williams Reveals Which Iconic Actress Left Her Starstruck: 'I Got a Little Tongue Tied'

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Meeting your heroes can leave you at a loss for words.

Michelle Williams hit the star-studded Critics' Choice Awards red carpet with best friend Busy Philipps on Sunday, but the Manchester by the Sea star revealed to ET that there’s one celebrity who recently left her starstruck: Diane Keaton.

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"I was at something recently and Diane Keaton was there and I got a little tongue tied," the 36-year-old actress admitted.

The Critics' Choice nominee also addressed her acclaimed new film, and why it seems to be resonating with audiences.

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"It is actually full of unexpected hilarity, there's moments in the movie that you can't believe it, you just find yourself laughing," Williams said of the Kenneth Lonergan-directed family drama. "It's so much like life, these sort of good and bad things happen in concert with each other."

Watch the video below for more from the film.

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