Actor Taye Diggs will join the cast of the as-yet-unnamed 'Grey's Anatomy' spinoff, reports Reuters. Diggs will star opposite Kate Walsh in the new series, which is expect to film its back-door pilot for release later this season. The episode will be scripted by 'Grey's' showrunner Shonda Rhimes, and will focus on the departure of Walsh's character Addison Shepherd from Seattle Grace.

Diggs has recently appeared in the cancelled series "Day Break" and was the title character in the series "Kevin Hill," but his most famous role was as part of the original Broadway cast for "Rent," where he met his future wife, Idina Menzel ("Wicked").