When a bike race leaves one pedestrian brain dead, interns Cristina and Izzie face an emotional crisis of conscience: how long does one wait before they start harvesting his organs? Cristina is all detached professionalism, but ever-hopeful Izzie prays for a miracle. Meanwhile, George avoids a flirtatious patient while Meredith copes with living with roommates and tries to dodge Derek's ever-increasing advances.