It was April 2004, and a 30-year-old Omarosa Manigault was minutes away from making her Jimmy Kimmel Live! debut. The first season of Donald Trump’s The Apprentice had just ended and she had emerged as the hit reality show’s villainous star. But before Kimmel even had a chance to announce her name, Omarosa fled the building, afraid that the host would subject her to a lie detector test.

“Oh, I’ve been thinking about that a lot lately,” Kimmel tells me more than 14 years later in his office a few hours before Tuesday night’s show.

“What happened was, my Uncle Frank lied about something,” Kimmel recalls, referring to the one-time fixture on his show who passed away several years ago. “And I thought it would be funny to give him a fake lie detector test on the air, something that he thought was real.”

Omarosa spotted the setup for the lie detector test and “decided that we were going to spring it on her,” Kimmel adds, “which, if you know anything about taking a polygraph test, that’s not how it works. It takes a long time. There’s no ding and no buzz. It’s a chart that they analyze afterwards. So that was preposterous just to start with.”

“But she stormed out of there and the show was live, so we had no guest,” he continues. “She was very angry.”

Asked what Omarosa, who just this week put out her tell-all book Unhinged about her time in the White House, may have been trying to keep secret about her early days working with Trump, Kimmel says, “I’m sure there was plenty that she was trying to hide.”

“If I had given her that lie detector test, who knows?” he wonders. “Gary Busey could be the president right now.”

Among the claims she has been making on her publicity tour for the book is the existence of a tape on which Trump can be heard using the “N-word” behind the scenes at The Apprentice. Other late-night hosts, including Kimmel’s network rival Stephen Colbert, have joked that this revelation is hardly surprising. “Finally, we have proof that the guy who refused to rent to black tenants, said that a Nazi-Klan rally had some ‘fine people,’ and called Africa a ‘shithole’ is a racist,” Colbert joked Monday night. But Kimmel sees things differently.

“If there’s a tape of the president using the ‘N-word,’ I think that’s a line in the sand—and maybe I’m wrong, I’m always wrong, so I’m going in with that caveat—but I think that’s a line in the sand that his fellow Republicans will not cross,” Kimmel tells me. “And I do not see them throwing the full force of their support behind the president if something like that is revealed. I really don’t. But I could be wrong.”

When Kimmel took the stage Tuesday night he didn’t waste much time before launching into the Omarosa story. “All hell is breaking loose in Washington,” he said, laying out the various revelations in the book, including the “N-word” charge. The host said that Trump is denying the allegations, joking, “In fact, he said some of his best friends are ‘N-words.’”

As for the tweet in which Trump called Omarosa a “dog,” Kimmel added, “Only Donald Trump would defend himself from something racist by saying something sexist.” Ultimately he said it’s hard to decide who is telling the truth. “Do we believe the lying, backstabbing reality star?” Kimmel asked. “Or do we believe Omarosa?”

“I remember thinking it’s better this way,” Kimmel tells me back in his office of Omarosa’s decision to walk out that day in 2004. “I didn’t want to have her on the show. The woman—there’s clearly something wrong with her. And the fact that Donald Trump hired her is really all you need to know about that guy and his organization.”

Even now, as Omarosa Manigault-Newman has become the hottest talk show guest in the country, with appearances on everything from Meet The Press to The Daily Show, Kimmel says he doesn’t want her on his show.

“They asked me if we should try to book Omarosa and I said no,” he tells me. “Because I think she’s just all over the place.” Of course, that doesn’t mean he won’t continue to talk about her in his nightly monologue: “The president calling a woman a ‘dog’ is not something you get to see every day of your life.”

Stay tuned for the rest of our interview with the Emmy-nominated Jimmy Kimmel, who discusses the origin of his “feud” with Matt Damon, the controversy over his recent interview with Kanye West, his bizarre Twitter fight with Fox News host Sean Hannity and much more.