EXCLUSIVE: Shannen Doherty Comes Across as Catty in Unauthorized '90210' Movie

Lifetime's unauthorized Beverly Hills, 90210 movie doesn't air until Saturday, but ET has a sneak peek!

The Unauthorized Beverly Hills, 90210 Story centers on the rollercoaster ride of the popular '90s program's first four seasons. The movie highlights the drama between cast members and could very well make Shannen Doherty come off as especially catty.

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In clips from the movie, Doherty (played by Samantha Munro) is seen getting too hot for TV in a makeout scene with Luke Perry (played by Jesy McKinney), and later we find her trying to fire an attractive extra that is getting too much attention from the male cast members.

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 told ET in 1991. "We fight and beat each other up."

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Doherty explained to us at the time the pros and cons of fame, which sometimes put unintended stress on their lives.

"Our audience is really into the show, but you get a little paranoid because you get psycho people writing to you, too," Doherty shared in 1991. "They think they're married to you, and they're going to come drag you back home, so it's pretty interesting."

The Unauthorized Beverly Hills, 90210 Story, also starring Max Lloyd-Jones as Jason Priestley, 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.

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While the project doesn't shy away from the unflattering details of the show's history, Lloyd-Jones told ET that, ultimately, the film is harmless and well-intentioned.

"We're not destroying anyone's lives here," Lloyd-Jones said. "I think it's good fun. It's nostalgic. It's going to be entertaining."