Dr. Robert Mason has been studying a mysterious phenomenon for over fifteen years: the reemergence of tens of thousands of red-sided garter snakes ? the world's largest concentration of snakes ? after a winter spent in a state of suspended animation in subterranean caverns.

This gathering each spring in the forests of Manitoba, Canada, is one of the most extraordinary events of the natural world and is the subject of study for Dr. Mason, a.k.a. the Snake Scientist.