What has been going on in New York while the Turtles have been scattered across the globe? A dangerous district attorney has come into power, and he's got a grudge against mutantkind. Backed by some powerful benefactors who have designs of their own for the city, he's doing everything he can to stoke hatred against the mutants. With the TMNT absent, someone needs to step in and stop this power grab-and figure out who is backing this nefarious new enemy.Enter Casey Jones! Jason Aaron completes his first story arc for Teenage Mutant Ninja Turtles, teaming with legendary artist Darick Robertson, co-creator of The Boys!