To catch a fish you have to think like a fish. Fly fisherman are always looking for the magic fly, one that will catch fish every time. There is no such fly. In this book I explain the merging of art and science. Flytying is an art. By utilizing fluorescent colored materials, and natural feathers and fur that reflect ultraviolet light you combine art and science. This is the magic bullet fly fisherman have been chasing after for hundreds of years now. By appealing directly to a fish’s sense of perception you increase the odds in your favor. Fish, birds, and some animals see colors in the ultraviolet spectrum that people cannot see. I show how to tie classic fishing flies with the proper materials, and colors. Woven throughout the book are true adventure stories from years of experimentation while On The Water! Henry Butler has been a successful nature photographer for fifty years, and a fisherman for over sixty.