Tim Gunn Says an Unnamed Supermodel and TV Host Once Told Heidi Klum to 'Quit' 'Project Runway'

Tim Gunn is opening up about the early days of Project Runway with Heidi Klum, and shedding light on those who may have cast doubts about the show's success.

On Friday, Gunn penned a heartfelt letter to his "TV wife," thanking her for transforming him "into a happier and more confident individual." In the note, published by Good Housekeeping, the television personality also revealed that an unnamed supermodel didn't think the show would take off.

He began by recalling how nervous he had been to get the show off the ground.

"You wrapped an arm around me, took my hand and said, "Don't be nervous. Relax. We're going to have an amazing summer," he wrote, before fast-forwarding to a time later in season 1 when he had to return the favor.

"This time you were nervous about how the show would be received," he wrote. "You had shown a preview to so-and-so (another supermodel and host of another fashion-related show) who said to you, 'It looks awful. Cancel the show and quit.' This time, I took your hand and we sat and huddled."

He continued, " 'Think about it,' I remember saying. 'She's nervous and jealous. You and this show are competition for her. She wants to make you nervous and upset. Trust me. There's nothing to be concerned about and everything to feel confident about.' You leaned over and kissed me. And we had a fabulous season!"

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Despite their obstacles, Project Runway became "a big hit," Gunn insisted.

"We made 16 seasons together! Remember the night of our Emmy win for cohosts? That show dragged on and on and on with our category being second to last," he wrote. "At every break, we snuck out for champagne, lots of champagne. By the time the show finally got to our category, we were bombed — nervous, jittery, laughing bombed. WE WON!"

Project Runway premiered in 2004, with Gunn, 67, serving as a mentor to the designers. Klum, 48, judged alongside Michael Kors and Nina Garcia.

In September 2018, the pair announced they were leaving the Bravo series after 16 seasons. Their newest venture, Making the Cut, debuted on Amazon last year.

Klum and Gunn previously spoke about why they decided to "jump ship" during a television press conference before the premiere of the new show.

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"Our imagination was bigger than what we were allowed to do," Klum said, according to The Hollywood Reporter. "Everything kind of fell apart." She said the move from Lifetime back to Bravo was either going to mean returning to the "same old same old" or it was an "opportunity to jump ship." She asked Gunn, "Do you want to jump with me?" Klum said, "It was scary…. We shopped it around and thought that Amazon was the best place, not only for the show but also for the designers."

Gunn added: "We couldn't break out of it because there was a fear — not among us, we're the ones who were thinking creatively and innovatively about what we wanted to do."

Season 2 of Making the Cut premieres on July 16.