Terry McGinnis defeated the evil A.I. controlling Neo-Gotham and asserted himself as the one true Batman, but his next battle will bring him to the remains of Old Gotham. Children are going missing and being swallowed by the city's old bones. Batman Beyond will have to go underground, led by a mysterious splicer named Kyle the Catboi, to find the children and confront the city's buried sins. What happened to the green of the city? What happened to magic? And what villains never left old Gotham? All these questions will be answered by the red-hot creative team of Collin Kelly and Jackson Lanzing (Batman - One Bad Day: Clayface, Captain America: Sentinel of Liberty) and Max Dunbar (Batman: Urban Legends).