In the conclusion of a two-part story, Addison (Kate Walsh) undergoes a profound personal crisis as she mulls over the possibility of moving to LA's Oceanside Wellness Center (thereby setting the stage for the Grey's Anatomy spinoff Private Practice). Back in Seattle, Meredith (Ellen Pompeo) learns that her stepmother Susan (Mare Winningham) is suffering from something far more serious than a bad case of hiccups. Alex (Justin Chambers) shows up for emotional support as Derek (Patrick Dempsey) performs emergency surgery on Ava (Elizabeth Reaser). And Burke (Isaiah Washington) and George (T.R. Knight) get quite an earful when they turn to Bailey (Chandra Wilson) for marital advice. ~ Hal Erickson, Rovi