Batman: Detective Comics Vol. 1

Something is terribly wrong with Batman. No matter the tests Bruce takes, nor the numbers he counts, the greatest detective in the world can’t pin down the source of this creeping dread—of his own inner demons and a looming mortality. Meanwhile, real demons roam the shadows as an ancient melody haunts the Gotham night. As Batman investigates the songs and the demons of Gotham, he is forced to confront the oldest question: Has there been a demon within him all along? And if so, what does it want...and why hasn’t it taken over yet?
Collects Detective Comics #1062-1065.