The Dragon Pool is not up to the standard of the more recent entries in the series. The writing is not as good, particularly earlier on, and it seems a little sketchy for 350 odd pages.
Hellboy has more than one girlfriend that likes to dig up old monsters, it seems, and having discovered something not human this one asks him for help after discovering here be dragons (one big Chinese worm one, lots of smaller instances of the zombie variety).
Liz is taking some time out, so it is Big Red, Abe, the Professor and some grunts that get to go and play with monsters, and cover Chinese military types, as well as a village of dragonish people.
(call it 3.25 perhaps)
3 out of 5