Tori Spelling has confessed to having sex with more than one of her "Beverly Hills, 90210" costars back in the day.

All was revealed when the actress agreed to take a lie-detector test for Lifetime’s upcoming event, "Tori Spelling: Celebrity Lie Detector."

The 42-year-old star, who rose to fame as Donna Martin in the popular 1990s series, was confronted with the question while discussing Brian Austin Green, who played her on-screen boyfriend David Silver.

After promising a “no holds barred” interview, English TV personality Louise Roe asked Spelling, “Did you have sexual relations with any of your co-stars on Beverly Hills, 90210?”

The mother-of-four eventually confessed: “Yeah, I just got chills. I was a young girl,” admitting she had been intimate with Austin Green, who separated from Megan Fox after five years of marriage in August.

“Brian and I were the youngest. We were 16. I remember the time I shook his hand. I had, like ... I fancied him.”

The revelation shouldn’t come as a surprise to "90210" fans, given Spelling mentioned her brief fling with Austin Green in her memoir.

Roe pressed, “Was there anyone else from the original cast that you had sex with?”

After removing actor Ian Ziering from the equation, Roe narrowed it down to Jason Priestley and Luke Perry but Spelling refused to spill on which co-star it was.

“I’m not going to tell you. Half my friends don’t even know this,” she said.

This article originally appeared on News.com.au.