TMDb/Grey's Anatomy TV Grey's Anatomy mourns the death of patient Katie, a poignant storyline evoking memories of Izzie and Denny's tragic romance. April 17, 2026 AceShowbiz - Grey's Anatomy delivered an emotionally wrenching episode on March 19, 2025, as fans witnessed the death of couples therapist Katie, portrayed by Samantha Marie Ware. This poignant storyline stirred strong parallels to one of the show's most iconic and heartbreaking romances between Katherine Heigl's Izzie Stevens and Jeffrey Dean Morgan's Denny Duquette.