Having completed their internships, Meredith, Cristina, Izzie and Alex now begin their first year as residents and are assigned a new group of interns, including Meredith?s half-sister Lexie (Chyler Leigh). Meanwhile, a demoralized George (T.R Knight) is forced to repeat his surgical internship and a lonely McDreamy (Patrick Dempsey) finds an unlikely ally in Mark (Eric Dane).
