In birding, a Big Year is seeing or hearing as many different species of birds as possible in a calendar year. Three men pursue the Birder of the Year title: Kenny Bostick, who's seen a record 732 in a past big year, Stu Preissler, newly retired, and Brad Harris, who narrates the story. Life gets in the way: Bostick's wife wants a baby, Stu's firm needs him for sensitive negotiations, and Brad, divorced and underemployed at 36, has an encouraging mom and a disapproving dad. They criss-cross the U.S. (including a trip to Alaska's westernmost island), follow migration patterns, and head for storms that force birds to ground. Who will win, at what cost, and with what rewards?