The going has gotten tough, and Ned ''Dog'' Oglivie has gone fishing. Fly fishing. For trout. All across America. At least until his money runs out . . .

Driven by tragedy to turn his back on human society, the Dog is on a quest to fish himself into oblivion. And he's nearly made it. Playing the back highways of America in a wounded old RV . . . provisioned with a supply of peanut butter sandwiches, bad cigars, and vodka-Tang . . . armed with a loaded pistol (for when the money runs out) . . . the Dog is nearly at the end of his tether when he rolls into little Black Earth, Wisconsin, intending to fish the yellow sally stonefly hatch . . . and finds a body instead.

Who killed Jake Jacobs, fellow fly fisher and late-coming agitator who was trying to save Black Earth Creek? Why was Jacobs disfigured in such a peculiar way? Why does the Dog give a damn? Can he rekindle his faith and interest in humankind? By caring about the death of a stranger, can the Dog recover his own life? Can he untie The Nail Knot?