Medical miracles are part and parcel of Fox's series House, as the titular doctor played by Hugh Laurie consistently diagnoses and treats rare diseases. But its Christmas episodes deliver a different kind of miracle with a festive backdrop of tinsel and mistletoe in the stark white hospital halls. Humble beginnings with ailing nuns in Season 1 transformed into more genuinely miraculous acts in Season 4, during which Cuddy (Lisa Edelstein) cuts off House's Vicodin supply. But it is the Season 5 Christmas episode that takes the cake, not only featuring the biggest "hallelujah" moment, but also turning into a critical touchstone for the show's favorite couple.