Inside Zac Efron and Vanessa Hudgens' Rollercoaster On-Set Romance: 'The Sun and Moon to Her,' Says “HSM” Costar in New Book

Lucas Grabeel and other 'High School Musical' alums spill on the costars' relationship almost 15 years after their 2010 breakup

Zac Efron and Vanessa Hudgens were one of the most iconic couples to emerge from the Disney Channel universe. Nearly 15 years after their breakup, new light is being shed on how their romance blossomed — and what it really looked like.

In Disney High: The Untold Story of the Rise and Fall of Disney Channel's Tween Empire by Ashley Spencer, High School Musical star Lucas Grabeel (who played Ryan Evans) shares new details on the early days of Hudgens and Efron's relationship.

Natalie Hart, who worked on casting the movie, recalled Hudgens, who was 16 at the time, being nervous ahead of her callback for the role of Gabriella Montez alongside Efron for Troy Bolton because he was "too cute."

"It was magic," she said of Hudgens and Efron's first scene together.

Related: Zac Efron and Vanessa Hudgens' Relationship Timeline

Once they were cast in the lead roles, the chemistry between them continued to build, and Hudgens is described to have been "head over heels" for Efron, who had a girlfriend at home.

He had been resisting the pull he felt to Hudgens until one night, he had a conversation with one of the movie's choreographers Chucky Klapow.

Klapow recalled Efron telling him: "I don't know what to do, man. Vanessa is super into me, and I have feelings for her, too. I don't want to do the wrong thing with my girlfriend. But I also don't want to shut Vanessa down and ruin the chemistry in the movie."

Related: High School Musical’s Chris Warren Shares 5 Things You Never Knew About the Iconic Disney Movies (Exclusive)

He encouraged the actor to go for it, and that same night, "Zanessa was born."

Grabeel recalled that Hudgens and Efron "came out [of the bathroom] holding hands," after she'd gotten upset. "I mean, it was so high school. It was like, 'He broke up with his girlfriend and we're together now.'"

The pair continued to date through the third film, High School Musical 3: Senior Year, which premiered in 2008, though there were "occasional breakups," per Disney High.

"He was the sun and moon to her," Grabeel recalled of their relationship, adding "poor girl" in reference to Hudgens.

Peter Barsocchini, one of the film's screenwriters, weighed in, too, with a memory. "I hear [Hudgens] dragging Zac into this office and then I just hear yelling," he recalled of one such fight on set.

Still, he reflected on how lucky the team was that the relationship didn't blow up earlier. "Do you know how long relationships last at that age? That was a real blessing to hold it together for three movies."

Related: Corbin Bleu Reveals There's a High School Musical Group Text — Here's Who's Still Chatting (Exclusive)

While the High School Musical movies were airing, the pair kept their relationship largely out of the public eye. At the premiere of the second movie in 2007, all Hudgens would tell PEOPLE was, "He's an amazing guy."

They called it quits in 2010 after five years together, and a source told PEOPLE at the time they were "still good friends." A few months later, Hudgens shed light on the breakup as she revealed that long-distance had proven to be too difficult for the pair. "When you don't have face-to-face time, it's just different," she said.

Both Efron, now 36, and Hudgens, now 35, have since admitted that they've lost touch, with Hudgens telling Cosmopolitan in 2020 she hadn't "seen or spoken to him in years."

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The actress later went on to date Austin Butler for eight years and is now married to MLB player Cole Tucker, with whom she welcomed her first child in July.

Efron's dating life has remained pretty private since his split from Hudgens, though he's been linked to costars including Lily Collins, Michelle Rodriguez and Alexandra Daddario.

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