76

You follow a dry, rocky creek bed, which means it's slower going than you'd like, full of twists and turns and the possibility of a blowout if you aren't careful. Up ahead in the sky, you spot a flock of pterosaurs, four or five of them, circling and occasionally diving, then rising again. It's too far to see what they might have in their dagger beaks.

Coming around a bend, you slam on the brakes. Before you lies a pond in which a couple of triceratopses struggle, uttering grunts and snorts, though their movements are sluggish. A pterosaur swoops down to strip the flesh from the corpse of another great beast, something so far gone that it's hard to tell what it once was—possibly a juvenile T. rex, you think with a shudder. Bones of other unfortunates jut up from the water.

Worse yet, Darien Vance's RV is sunk up to its axles in the pool, with Casey and Skyler looking out the passenger-side doorway at Vance.

There he is, floundering knee-deep in the pond. Sweat drips from his flushed, terrified features. Black gobs spatter his lower half. "Guth," he shouts. "Watch out! It's a tar pit beneath the surface."

Yikes! Vance isn't kidding. The foul odor rising from the cesspool is due to more than carrion. You vaguely recall learning that a "tar pit" isn't actually filled with tar. But what the hell is that stuff? You can't quite remember. Some sort of noxious chemical brew—one not to mess with.

Tar Pit