Dr. Mark Sloan arrives in Seattle to try to convince Addison to continue their relationship, and is greeted with a punch from Derek, just for flirting with Meredith. Dr. Webber allows Sloan to assist Derek in a risky surgery to fix a teenage patient with facial tumors. Preston learns that Cristina still leases her apartment. Izzie treats a patient with spontaneous orgasms. Meredith goes to see her father for the first time in twenty years and is left unsatisfied with his answers about the past. George finally tells Meredith how he feels about her.