Everyone seems to be having a Merry Christmas except the people at Seattle Grace. Izzie (Katherine Heigl) can't get into the holiday spirit because she's still p.o.'ed at Alex (Justin Chambers), who for his part is convinced that he'll fail again when he takes his board exams for the second time. Back at the hospital, Bailey (Chandra Wilson) maintains her backbreaking schedule despite her pregnancy; George (T.R. Knight) can't help but feel that his patient's obnoxious relatives are the root cause for her gastric ulcer; and Cristina (Sandra Oh) and Burke (Isaiah Washington) have a theological argument while trying to persuade a 10-year-old to undergo a heart transplant. Finally, though Derek (Patrick Dempsey) and Addison (Kate Walsh have reconciled for the umpteenth time, it doesn't last long--a fact that doesn't make Addison happy, but which may turn out to be the best Christmas present that Meredith (Ellen Pompeo) ever had. ~ Hal Erickson, Rovi