So who's the first friend they called on to stop by their series? Spelling shared the news on Twitter Tuesday:
Joe E. Tata played everyone's favorite boss and surrogate father, Peach Pit owner Nat Bussichio. Nat was a fixture throughout the Fox show's 10-season run, and he even walked Donna (Spelling) down the aisle in the series finale.
Which other Beverly Hills, 90210 alums should guest-star on Mystery Girls?
Get a behind-the-scenes look at the series below: