The titular J.H. O’Donnell and Hellboy explore an extensive occult library and extensive occult things happen. Laughter and atmospheric horror ensue.
What really works in this one is the sense that this is just a part of a story, or, perhaps, just a story in a much larger world. You rarely get anything close to understanding at the end of a story in the world of the BPRD. We see the monster and some of the impact he has, but the how and why are never fully explained.
I don’t want to give the spoiler warning and the short description of the comic here. I could, but why would I defuse the tension and humor? Instead, I will just say that this one is easily worth your time.
Five shambling horrors out of five.