Derek Hough Shares Top Advice for DWTS' Season 35 Contestants

Derek Hough Reveals His "Massive" Personal Gift for Hayley Erbert on Mother's Day

Derek Hough wants these celebs to leave it all on the dancefloor.

As Dancing With the Stars' season 35 cast continues to come together one celebrity reveal at a time, the longtime pro-turned-judge shared one very important piece of advice for the likes of Ciara Miller, Maura Higgins and Jackson Olson as they dust off their dance shoes and prepare to compete for the coveted Mirrorball Trophy.

"You better get ready to work. That's it," Hough exclusively told E! News June 7 at the Tribeca Film Festival premiere of his new movie The Symphony of Dance in New York City. "I mean that jokingly, but also seriously."

However, the 41-year-old has no concerns that the three previously announced celeb contenders aren't willing to shed blood, sweat and tears as they begin training for the ABC reality competition series' upcoming season.

"That's who we're casting now: People who are in it to win it," Hough noted, "who want the full process, who want the full experience. So, be prepared."

And while winning is nice and all, Hough reminded the stars that the ballroom journey is about much more than prize money and bragging rights.

"It's the most fulfilling experience you'll ever have," he advised, "if you really put your everything into it."

But with the DWTS premiere still several months away, Hough is staying plenty busy promoting his latest passion project, his and wife Hayley Erbert's deeply personal documentary The Symphony of Dance. The intimate film follows the couple's 2023 tour amid Erbert's life-threatening health scare and recovery from a cranial hematoma.

Though, according to Erbert, they didn't initially set out to tell such a personal story.

Roy Rochlin/Getty Images for Tribeca Festival/Michael Loccisano

"We never intended on filming a documentary," the 31-year-old—who welcomed daughter Everley, 5 months, with Hough in December—told E! of the project. "It was actually [director] Jason Bergh who approached him and he was like, 'Hey, I just want to come shoot your first rehearsal.’ Then it turned into, 'We also want to shoot you going to this doctor's appointment and this rehearsal and this.’ It just turned into a story. It felt really authentic, and that was why it felt like the right time."

Remaining "raw" was key to the couple's creative process, as Hough explained they didn't want the film to "feel produced."

"It doesn't feel like we created something that was inauthentic," he added, "and if we could share this with somebody, and maybe one person gets a little bit of hope from it or a little bit encouragement or sees some inspiration in this, then beautiful."

While fans wait for more cast reveals, keep reading for fascinating secrets behind DWTS.

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