Frog was an orphan with no name. He was one of many children to be taken in by the Sewer King. The children were subjected to torture and deprevation. He molded them into slaves and ordered them to pick pockets for him. In the night, they left the sewers and took what they could. The children were subjected to fear of ligh so they wouldn't escape. Frog, however, was caught by Batman. He soon discovered that Frog was unwilling to speak but was his only lead. Batman had Frog lead him to the Sewer King's quarters. Batman stopped the Sewer King and freed the children. Frog and the others were put up for adoption and found new families to live with.