S8, E4: Dr. Susan Lewis arrives, looking for work in the Chicago area again. Greene hires her, over Weaver's objection. Chen nervously attends a risk management review, accompanied by the unforgiving Weaver, to discuss a patient who recently died under Chen's supervision. Upset that Weaver, who was unreachable at a crucial moment in Chen's unsuccessful surgery, supports demoting her from chief resident, Chen quits. Meanwhile, busy with a lifesaving surgery, Benton must ask Roger to take care of Reese after school. Corday struggles with the desperate case of a young, abandoned boy with a rare and chronic disease. And Kovac is surprised when Nicole, the beautiful French waitress with whom he flirted, comes to the emergency room looking for him.