As noted in the previous review, Nance and Tarvik from the Magic Bubble world on the Olympic Peninsula followed Our Heroine Claire Carmody when she found a way out. Big difference, however: Nance came with Claire. Tarvik took care of some business in the bubble first: killing Erlan, collecting his father Kovat's sword and, he thinks, accidentally killing Alakar and Ober in the process. If you've read the synopses of the later books, you know he failed to kill Alakar, altho you don't find that out reading this one.
Tarvik may be illiterate, but he's quite capable. He's offered a ride while looking at the trucks go by on the road. That leads to a meal at a diner, and another ride into Seattle, a name he remembers Stargazer using to describe her home. From a backpack and empty wallet she left behind, he digs out a business card for the Mudflat Community Center and with that, he shows up on her doorstep (well, for her job, anyway).
And that's not the full list of people sneaking out of the bubble and showing up in Mudflat. People are disappearing from Mudflat, too. Tarvik moves in with Nance and Claire. Jimmy, Claire's cousin, enamored of Nance is hanging around a lot, too. The four are assigned to try to track down the disappeared people in a puddle of evil in the other mountain range in Washington State: the Cascades. After a couple day's hike from the trailhead in Stevens Pass, they find a truly nasty beastie that matches the description of the lifedrainers from the first book. How did _that_ get out of the bubble? And why is it disappearing people from Mudflat?
The four, in true D&D fashion, puzzle it all out and kill the beastie, but when people go back to deal with the corpse it is gone. And then people start wondering how much of it was even real, while our crew are still busy trying to figure out who is responsible for all this.
Of course the party responsible does show up in a very flashy fashion, and Claire, with some difficulty, deals with the problem. Then Mudflat's infrastructure steps in to make sure there isn't any suspicious mess left over for ordinary folk to discovery. Nevertheless, there are some loose ends, which will inevitably unravel, further connecting the Magic Bubble world from book 1 with Mudflat.