Like sex or death, fly fishing looms large in Gierach's universe as one of life's eternal mysteries, vast and unkowable- and perhaps it's better that way, especially when you've been standing in a river for hours and have nothing to show for it. But as Gierach's witty and sharply observed meditations on the fishing life prove, the journey is the destination, and the promise of bigger trout and undiscovered streams is irresistible.

Gierach's quest take him from quiet home waters in Colorado across the West to places like Utah's Green River, Wyoming, and British Columbia. Philosophical, evocative, and with his usual dry humor, Gierach contemplates mayflies and men, less-loved fishes like grayling and gar, the finer points of "expertizing", and the practicality of raising roosters for hackle feathers. In the end there may be more questions than answers, but that's OK- "I don't know exactly what fly fishing teaches us", says Gierach, "but I think it's something we need to know".