Batman: Detective Comics, Vol. 1: Mythology — Peter J. Tomasi

Alfred Pennyworth...attacked at Wayne manor! Who�s hunting those closest to Batman? Commissioner Gordon calls in the Dark Knight Detective when there�s a murder at the Gotham City Aquarium-staged to look exactly like Thomas and Martha Wayne�s crime scene, right down to the playbill and pearls. How does this bizarre homicide tie into the shadowy monster that attacks Dr. Leslie Thompkins? This creature looks to wage a war on Batman-and it�s using Joker gas to do it! Collects Detective Comics #994-999.