Spinning out of the shocking events of Heroes in Crisis, writer Joshua Williamson (The Flash) and artists Guillem March (Gotham City Sirens) and Rafa Sandoval (Catwoman) team up the two greatest detectives in the DC Universe for an epic crossover event!

After the tragic deaths at the superhero recovery facility Sanctuary, both Batman and Flash have faced incredible losses--friends and loved ones who have suffered consequences because they too, put on masks and wanted to be heroes.

But now someone wants these superheroes to think about the true price of what they do. The ultra-powerful but unstable metahuman known as Gotham Girl has attacked the Flash Museum in Central City, pulling Batman and Flash into a mystery...and a race against time.

What does she want? Can these two damaged heroes stop her before she kills someone--or destroys herself? Or will yet another hero pay the ultimate price?

Plus, Batman and Flash aren't the only heroes hit hard by the events at Sanctuary: Green Arrow and Black Canary must fight back their own grief as they face down a new threat. But will Ollie's mourning lead him down a dangerous path?

Collects Batman #64-65, The Flash #64-65, The Flash Annual #2, and Green Arrow #45 and 48-50.