After Abby leaves the room for a second, an infant disappears from the hospital. After spending the night at her place, Carter is shocked to find out that Rena is a 19-year-old undergraduate. Greene gets his competency results--he passed (was there ever any doubt?). Malucci and Mark treat a young boy injecting steroids who is frightened of his father. Legaspi has been accused of sexual misconduct by the teenager who caused the train crash. Weaver is more concerned with hiding their relationship, so Kim dumps her.