The singer turned actress will be part of the two-hour season finale which has just been announced to take place on May 20.
"Grey's Anatomy" is recruiting another young actress to appear in one of the episodes. After it was announced that Demi Lovato will take a guest-starring episode, it is revealed that Mandy Moore will also stop by the medical drama for a stint that will air in May.
Similar to Lovato, Moore will play a patient at Seattle Grace. While Lovato's schizophrenic character falls under the care of Justin Chambers' Alex and Jessica Capshaw's Arizona, Moore's Mary will be treated by Chandra Wilson's Bailey.
Apparently this would be a big episode since the May 20 is the season six two-hour finale. According to TV Guide which was the first to report, sources said Moore is just one part of the kind of finale that executive producer Shonda Rhimes loves keeping under wraps. Thus, there would be no more details surrounding her role released.