The Adventure of the Naked Guide

"The earth is hollow—a trackless primordial wilderness. It's also the new front in the Great War. Here, the British spy Lucy Harker—Dracula's daughter—must locate Britain's missing vampire slayer—her own mother. Then she's separated from her lover, the vampire spy Carmilla, and captured by Germany's most brilliant scientist, the sinister Dr Krüger. Now, Agent Harker may discover her most dangerous opponents are on her own side" --