Allied with the mysterious new Shush, Man-Bat will stop at nothing to unleash his Cult of the Bat and its thousands of poisoned bats on Gotham. Batman and Robin have enough on their plate when Flatline, Damian's crush from the Lazarus Tournament, shows up with her own mysterious plans. Can the three unlikely allies stop Man-Bat and Shush in time? And what does Gotham City High School have to do with it?