Thiessen, who starred as Valerie Malone for six seasons starting around the time of Shannen Doherty's departure in 1994, said her contractual obligations for her Netflix series, Alexa & Katie, are keeping her hands tied.
"I'm actually shooting season three of Alexa & Katie right now. So I am working at the moment and busy," she said. "I'm literally in the middle of my season, and I go 'til September."
"My shoot schedule sadly won't allow [me to be a part of it], but I wish them well," she added. "I'm sure it's going to be great."
"I don't know much about it but I know people are going to be excited," she said of the upcoming series.
The new show is described as a serialized drama following heightened versions of the Beverly Hills, 90210 original cast members — Jason Priestly, Shannen Doherty, Jennie Garth, Ian Ziering, Gabrielle Carteris, Brian Austin Green and Tori Spelling. It's based on the real lives and relationships of the classic show's main cast members.
Actress Vanessa Lachey was recently announced as the newest cast member of BH90210. As first reported by Deadline, Lachey will star as Camille, the high-powered publicist wife of Priestley, who is balancing her demanding career with the hopes of starting a family of her own.
In addition to Lachey, La La Anthony was also announced as a new cast member, playing the role of Green's wife, Shay, a superstar hip-hop/pop singer. Her character is described as the "breadwinner of the family while her Mr. Mom husband watches over their three kids. Shay has become used to being the center of attention, but can still be surprisingly down to earth."
Garth told PopCulture.com about the new show, revealing that the concept is meant to put a new spin on TV reboots.
"It's uncharted territory... Where an entire ensemble is playing themselves, or versions of themselves, let's say. It's kind of daunting, at the same time, very, very exciting and creatively fulfilling," she said last month, adding that fans can expect to relate to her character's journey.
"My character in the show [is] dealing with relationship issues, which I am no stranger to, marriages and divorces, teenage daughter and the reality of being who she is, living the life that she's living," she said.
"It's a really interesting look into someone's life that you think is so different from yours, but I think you'll come to find out that these characters that we're creating are all going to be relatable to people on different levels," she added.
BH90210 will premiere Wednesday, Aug. 7 at 9 p.m. ET on Fox.
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