While institutionalized in Arkham, Killer Croc meets Sybil Silverlock, a woman with dual-personality disorder. He bonds with her softer personality, and she shows him a picture of her daughter, Olive. Sybil has him promise to look after Olive if he ever gets out. After the destruction of Arkham Asylum, Killer Croc escapes and travels to Gotham Academy, where he watches over Olive, and tells her about her mother, who was rendered comatose by the asylum's destruction. After Batman confronts them, Olive and Killer Croc escape to a swamp. Before parting, he tells her that, if she is like her mother, to come and find him one day.