The Workmen: Biff who?

"Come on, let's go," Jon said, figuring he'd just figure out how to help Biff later, after they got away from the workmen and this warehouse. "Look...I'm not sure who I am...or who you are. But I'm not going with you until you tell me what is going on," Biff said, calmly...probably because he didn't know the danger they might be in. "Your name is Biff..." "What kind of a name is Biff?" He asked. "I didn't name you...we have to get out of here before they find us." "They who?" Biff said. "I don't know," Jon said. "But..."