Richards, 41, will play Gwen, described as a sexy, wealthy socialite who graduated from West Beverly High School. Gwen is the head of a very powerful and very exclusive women's club that Naomi (AnnaLynne McCord) will do anything to be a part of. That is, until she realizes this group is a grown-up version of a Mean Girls-esque clique.
The new season of 90210 premieres on Oct. 8. Richards' episode will air Nov. 26.