|Affiliation:||The Sewer King|
|Only Appearance:||The Underdwellers|
|Appears in:||1 Episode|
Jack was part of The Sewer King's child-slavery racket.
Jack and the children had become very accustomed to darkness, having done many hard tasks for the Sewer King. As part of the racket, they gathered around his throne for their usual lesson. The Sewer King had a strict rule of making no noise, not even talking, and heard someone yell after being hit with a shovel. He pointed to Jack as the culprit, and as punishment, sent him into a room with bright lights where he would have to spend a few hours, much to the other children's horror. Once Batman ended the Sewer King's operation, Jack and the others were taken in by social workers.