Batman: Nightwalker by Marie Lu (DC Icons Series #2)
The Nightwalkers are terrorizing Gotham City, and Bruce Wayne is next on their list. One by one, the city’s elites are being executed as their mansions’ security systems turn against them, trapping them like prey. Meanwhile, Bruce is turning eighteen and about to inherit his family’s fortune, not to mention the keys to Wayne Enterprises and all the tech gadgetry his heart could ever desire. But after a run-in with the police, he’s forced to do community service at Arkham Asylum, the infamous prison that holds the city’s most brutal criminals. In Arkham, Bruce meets Madeleine, a brilliant girl with ties to the Nightwalkers. What is she hiding? And why will she speak only to Bruce?