A mystery in Batgirl's past that has been building for years is about to be revealed! Who is Batgirl's mother? Batgirl is about to find out, but her mind will be on other things, as she's trapped in a life-and-death struggle with her animalistic "brother" Mad Dog! And when we say "life-and-death," we mean it! No tricks. No jokes. One of these characters will die at the hands of the other, but who will live and who will survive? Will Batgirl's mother help?