Michael Fassbender Admits He Was Intimidated by Kate Winslet in 'Steve Jobs'

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Steve Jobs star Michael Fassbender has praised co-star Kate Winslet for being a "great partner" in making the film, but he also admitted to being intimidated by the Oscar winner early on in the process.

As Winslet hails from the U.K. and Fassbender is from Germany, they both had to master American accents which, according to Fassbender, Winslet did almost immediately.

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"She had it on the first day on the read thru," Fassbender told Winslet in an ET sit-down. "I remember at the read-through when you started speaking I was like, 'Oh no! I'm so far behind!'"

In the film chronicling the drama that preceded three of Jobs' iconic Apple product rollouts, Winslet plays Jobs' marketing chief Joanna Hoffman. Hoffman had a reputation for being one of the few people who could successfully interact with Jobs, with their relationship acting as somewhat of a "work marriage."

Mirroring her character, Winslet played a maternal role with the cast off-screen as well.

"I definitely felt I had to look after you," Winslet told Fassbender, who plays Jobs.

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Seth Rogen plays Apple co-founder Steve Wozniak, and he said getting the inventor's approval was an unexpected surprise.

"That was nice!" Rogen said. "It's like a bullet I didn't know I dodged until it was fired at me. And then afterwards I heard he liked it. I was like, 'Oh! He could have hated it! That would have sucked.'"

One person who hasn't been a fan of the biopic is Apple CEO Tim Cook, who described Steve Jobs and Alex Gibney's documentary, Steve Jobs: The Man in the Machine, as "opportunistic" during an appearance on Late Show With Stephen Colbert.

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"I hate that," Cook said. "It's not a great part of our world."

Steve Jobs screenwriter Aaron Sorkin later fought back, telling The Hollywood Reporter, "If you've got a factory full of children in China assembling phones for 17 cents an hour, you've got a lot of nerve calling someone else opportunistic."

By the time he sat down for our interview, Sorkin had calmed down and apologized for the comment.

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"I think that Tim Cook and I both went too far," Sorkin said. "I apologize to him and I hope when he sees the movie, he enjoys it as much as I enjoy his products."

Steve Jobs opens Oct. 23.