She sat on the witness stand Thursday and answered prosecutors' questions about her alleged assault by Bill Cosby with an uncharacteristic reserve.

But seconds into Janice Dickinson's face-off with defense lawyer Tom Mesereau on the fourth day of testimony at Cosby's retrial in Norristown, the 63-year-old supermodel's trademark, reality TV-honed pugnacity had returned.

Dickinson – one of Cosby's most vocal critics and a former fashion plate better known these days for her late-career turn on shows like America's Next Top Model and Celebrity Rehab – snarled and sneered her way through an electric, hour-long cross-examination Thursday as Mesereau dug deep into her colorful past.

But, facing repeated attempts to discredit her, Dickinson refused to give an inch.

"So what?" she snapped at him at one point. Cosby "raped me in Tahoe."

There may be no better-known name than hers in the pantheon of the more than 60 women who have come forward since 2014 to accuse Cosby of sexual improprieties. The self-styled "world's first supermodel" helped kick off that wave when she first aired her allegations publicly that year in an interview with Entertainment Tonight.

But with her Hollywood allure and tales of modeling trips to exotic locales, Dickinson cut a far different figure than the other Cosby accusers jurors heard this week, all of whom had long left their acting, modeling or partying days behind. That list included Lise-Lotte Lublin, a sixth-grade teacher from Las Vegas, who said Cosby drugged and sexually assaulted her in 1989. She also testified Thursday.

Mesereau, in questioning Dickinson, sought to take advantage of her outsize – and at times messy – public persona.

He balked at her account of a 1982 trip to Nevada, where she said Cosby offered her a pill for menstrual cramps that knocked her out and then assaulted her in a hotel room.

She stood firm in her story, calling Cosby a "monster" and punctuating her answers with a series of icy glares at the 80-year-old defendant.

The lawyer accused her of wanting to see Cosby convicted to bolster a defamation lawsuit she has filed against his client. The supermodel pushed back, saying all she wants is an apology from Cosby to all his victims.

And when Mesereau, seemingly out of nowhere, interrupted to ask Dickinson whether she ever spread false rumors that she was pregnant in the early '90s with Sylvester Stallone's child, the supermodel responded with a coarse frankness laid down like a challenge.

"I was pregnant. I had sex with two men that month. [Stallone] wasn't the only contender," she said. "After the DNA test, he was not the father of my child. Thank God."

As usual, Cosby sat silently. But the antagonism between his lawyer and his accuser was so charged, it seemed to inspire open antipathy in others. As the court broke for lunch halfway through Dickinson's testimony, Cosby spokesman Andrew Wyatt lashed out at lawyer Gloria Allred as she answered reporters' questions on the courthouse steps.

"You're a highly paid, so-called civil rights lawyer," Wyatt heckled, shouting over her answers. He later referred to Allred, who represents three of the accusers to testify so far at the trial, as "Gloria Awful-red" and her daughter, Lisa Bloom, who is Dickinson's attorney, as "Lisa Blasphemous Bloom."

Amid those bouts of rancor, Dickinson told a sobering tale on the stand.

Under questioning from Assistant District Attorney M. Stuart Ryan, she explained she had just begun to find success as a working model in 1982 and was at a photo shoot on Bali, in Indonesia, when she received a phone call from Cosby inviting her to meet him in Reno.

"He offered me transportation. He said, 'Will you fly economy?'" Dickinson recalled. "I said, 'No, I will not. I fly first class.'"

Ostensibly, the purpose of her trip was to discuss a possible future career as a singer – one that Dickinson explained "never got off the ground because I can't sing."

When she complained of cramps that night over dinner, she said, Cosby offered her a blue pill. She said she began to feel woozy and lightheaded as he later led her to a hotel room.

"He got on top of me. His robe opened," Dickinson said. "He smelled like cigars, and espresso and body odor."

She told jurors she was powerless to resist and felt immobile.

"I remember thinking, 'What the heck is he doing?' I was just in shock," she said. "Here was 'America's Dad' on top of me — a happily married man with five children. I remember thinking how wrong it was – how very, very wrong it was."

But, Mesereau noted, Dickinson made no mention of sex with Cosby that night in her 2002 memoir, No Lifeguard on Duty – a book that the lawyer pointed out, in an aside, was ghostwritten by Pablo Fenives, who also wrote O.J. Simpson's 2007 tell-all, If I Did It.

Instead, the book says Dickinson drank herself to sleep that night in Tahoe with cognac and Quaaludes after Cosby left her at the hotel room door.

"It's all fabrication," Dickinson spat back. "It was written by ghostwriters. I wanted a paycheck."

Mesereau pounced: "So you made up a story about Bill Cosby because you wanted a paycheck?"

Lublin, who followed Dickinson on the stand, said it was the supermodel's own Cosby story that helped her come to terms with the experience she had with the comedian in 1989. Prosecutors hoped her testimony, like that of the four other women who said Cosby attacked them, would bolster the account of their central accuser, Andrea Constand, when she is expected to testify Friday.

Lublin recounted meeting Cosby for an acting lesson at the Elvis Presley suite at the Las Vegas Hilton, where he offered her two drinks that made her feel woozy.

It wasn't until Dickinson and other women came forward, she testified, that she was sure something more had happened to her that night – a point Cosby lawyer Kathleen Bliss stressed in cross-examination.

Still, Lublin left the Norristown courtroom standing firm  — though perhaps not as memorably as Dickinson had done before her.

As the supermodel was dismissed by Judge Steven T. O'Neill, she stopped to address him.

"I think you've been great," Dickinson told the judge, quipping: "And I swear, Law and Order is my favorite program."

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