As the assistant to Margo Maloo, Charles has gone on assignment in some pretty interesting locations. He's been to a vampire's lair, an ogre's den, and even a monster grocery store! But he's never been to the Downside, Echo City's underground monster metropolis that is super mysterious and DEFINITELY off-limits to kids. But a settlement of giant spiders is about to be dynamited by unwitting construction workers—and, coincidentally, one of those giant spiders "accidentally" bites Charles. His cure and the spiders' salvation lie in the Downside—if Charles and Margo can make it in time.

Graphic novel.