Megyn Kelly previewed tonight's first presidential debate on The Five this afternoon, specifically discussing how moderator Lester Holt will approach the highly-anticipated event.

Kelly said no topic or question should be off-limits for either candidate, since they're each seeking the "highest office in the land."

"No matter how offensive the question is, they have to handle themselves with poise," said Kelly, adding that Bill Clinton's past infidelities, for example, should be fair game as long as the subject is handled "gently and professionally."

Kelly said she agrees that Holt should not be "the mother of all fact-checkers," and that Hillary Clinton should be able to call out Donald Trump's statements on her own. 

She said Holt is in a "lose-lose situation," adding that he should ask tough questions, be fair to both sides and then "get the hell out of there [and] stay out of it."

Overall, Kelly said the event is so highly anticipated - with 100 million expected to tune in - because the two candidates are so different and there's a belief that "anything can happen and probably will."

Watch her thoughts above and don't miss Megyn and Bret Baier's coverage, starting at 9:00pm ET, followed at 11:00pm ET by a special Kelly File, with Trump campaign manager Kellyanne Conway, Clinton campaign press secretary Brian FallonDana Perino, Chris Stirewalt and Marc Thiessen.

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