The Hellboy series is published as a series of self-contained but still inter-connected mini-series and one-shots. This mini-series represents issues 33-35 in the ongoing Hellboy meta-series. It was preceded by Hellboy: Darkness Calls and followed by Hellboy: In the Chapel of Moloch.
Collected Editions:
Hellboy: The Troll Witch and OthersHellboy: Library Edition Vol. 4
