Izzy returns to the hospital for the first time since Denny's death. Meredith dates Derek and Finn and tries to come to a decision. Mark is in Seattle to win Addison back.

Tropes

• Abuse Mistake: A young girl comes in with multiple pretty bad injuries. The assumption is that her foster parents are beating her, but it turns out that she doesn't feel pain and therefore does dangerous things and doesn't realize she gets hurt.
• Feel No Pain: Alex young patient doesn't feel any pain. That leads to ignoring bad injuries because she doesn't realize it's bad.
• Heroic BSoD: Izzy stands in front of the hospital the entire day because she can't go inside.