Mandy Moore will be checking into Seattle Grace for the two-hour finale of ABC’s Grey’s Anatomy, TVGuide.com has learned exclusively.
The 25-year-old singer-actress (A Walk to Remember) will play Mary, a patient being treated by Bailey (Chandra Wilson) in the May 20 finale.
Sources said Moore is just one part of the kind of finale that executive producer Shonda Rhimes loves keeping under wraps, so no further details on her role were released.

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