Superman / Batman: Public Enemies (Apr 2004,DC)

iconic super-heroes unite when longtime Superman enemy Lex Luthor, now president of the United States, accuses Superman of a crime against humanity, and assembles a top-secret team of powerhouse heroes to bring Superman in -- dead or alive. And in the second storyarc, prepare for the arrival of Supergirl! Batman has discovered something strange on the bottom of Gotham Bay, which leads him to a mysterious and powerful teenaged girl bent on destroying Gotham City! What's her connection to Superman