The Ehrich Weisz Chronicles: Metamorphosis by Marty Chan

In this third, and final book of the Ehrich Weisz Chronicles, Ehrich must make good on his promise to his brother Dash that they will return to their home dimension frm their current position in the alternate New York, where immigrants are not just from different lands ? but from different dimensions. When an attack by the Dimensionals kills passengers and crew of the airship Oriental Clipper, Demon Watch Commissioner Thomas Edison promises to electrocute 54 Dimensional, unless Ehrich and his friends can stop him, while thwarting warlord Ba Tian's planned invasion of New York.