Lifetime is giving Beverly Hills, 90210 the tell-all movie treatment this fall for the show's 25th anniversary, and ET was on the set of the classic primetime soap in 1991.

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"A year ago I was shoveling asphalt and, a year from now, I could be doing it again," Luke Perry told ET at the time.

The first half of 90210's 10-season run was particularly volatile, and ET was there for a taste of the real-life drama that could have tanked the show.

"We're like brothers and sisters," Jennie Garth said. "We fight and beat each other up."

Jennie and co-star Shannen Doherty famously had a rivalry early on, which is captured in Lifetime's TV movie. Samantha Munro plays Shannen in the behind-the-scenes throwback, and she dished to ET about the actresses' tumultuous relationship.

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"The fist fights were real and there were a lot of them," Samantha said. "They'd been feuding and bickering. I know there was some bad blood between them, and they'd fight it out in the parking lot."

While the cast may have contained a few fighters, there were plenty of lovers too, as Abbie Cobb, who plays Jennie, explained to ET.

"Apparently there was a lot of [hooking up] going on," Abbie said. "There's lots of kissing."

By the end of the second season, the cast members were icons, and their success may have brought them closer together.

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"I think the guys ... it seemed like it was a great time," Max Lloyd-Jones, who plays Jason Priestley, said. "They are still very good friends today."

The Unauthorized Beverly Hills, 90210 Story, also starring Jesy McKinney as Luke Perry, David Lennon as Ian Ziering, Ross Linton as Brian Austin Green, Michele Goyns as Gabrielle Carteris and Alyssa Lynch as Tiffany Thiessen airs October 3 on Lifetime.