During a stake-out at a construction site, Batman and Robin catch a gang of mobsters trying to sabotage it, as the wealthy architect refused to be extorted by them. While all but one of the mobsters escapes, Batman catches the straggler and demands the name of his boss. The criminal refuses to speak to him or the police, but when Batman shows he's not joking, the criminal blurts out the name "Billy Marin", a name that seems to disturb the Caped Crusader. When they return home, Robin is left wondering who Marin really is, but Batman insists that Robin stay out of this one: he works alone for the time being. Following Batman's departure, Robin and Alfred Pennyworth use the Batcave's criminal database to determine the real identity of the crime boss. Robin discovers that Marin is really an alias for Tony Zucco, someone he crossed paths with nine years ago in an event which changed his life.