The 13th season of Grey's Anatomy concludes with a disaster episode that largely follows a single cast member, Dr. Stephanie Edwards, after she finds herself trapped with a patient who is revealed to be a rapist. Complicating an already distressing situation is a young girl named Erin, who wanders away from her parents and winds up trapped with the two of them, which leads to Steph setting the man on fire in order to save them both. Of course, the fire then spreads out of control, leading to the evacuation of much of the hospital while Steph battles the flames so she and Erin can get up to the roof.
Ultimately, both Steph and Erin are OK, but the near-death experience brings Stephanie a moment of clarity, and she realises she doesn't want to spend her life in a hospital saving lives instead of living her own. However, while this is the last episode where Stephanie appears, her departure doesn't wind up leaving as much of a hole as it should have; she is rarely mentioned in the following seasons, even by her best friends.