She is the first female lead in the 55-year-old, science-fiction series and her inaugural episode premiered Sunday night.
"It's an unusual journey," Whittaker told UPI about her new life under an intense spotlight, noting this level of attention seems similar to that afforded to actors who play comic-book heroes and super spy James Bond.
"You are famous before you've stepped on set, so you've made this huge life choice for your family forever and yourself and your career and you are a familiar face before you've kind of accepted yourself what that will mean," she said.
Whittaker was confident she could play the iconic character, but said she experienced some anxiety about living up to fan expectations.
"Back when I was revealed, I hadn't shot any of it yet, so I was still like: 'Please be good! Please be good! Please don't mess this up!'" she laughed.
"What I've had previously is, 'I recognize you maybe from that, maybe from that.' This is, 'I know who you are,' and that's an adjustment. But it's been a very warmly received moment. So, no horror stories yet."
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Writer-producer Chris Chibnall said in a separate interview that the fan reaction to Whittaker's casting was better than he expected, even though some people balked at a woman taking over the role of the titular Time Lord.
"We thought it would be a massive, 80/20 against and it was 80/20 in favor, really," Chibnall said.
"Because people don't like change. But it turns out people DO like change, which is interesting."
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