From a Pulitzer Prize-winning Sports Illustrated journalist comes a fascinating exploration of what it means to be a superfan, featuring personal profiles and cutting-edge psychology.

There are fans, and then there are fanatics. In this wondrously immersive look at American sports fandom, George Dohrmann travels the country to find out what makes a superfan. In Minnesota, he meets newly minted generals of the Viking World Order; in Oregon, he shares a few beers with a lone soccer fan who single-handedly amassed a cheering section 4,000-strong for the Portland Timbers; in Illinois, he talks with the parents of a five-year-old boy whose hatred of Tom Brady went viral on YouTube. Through these and other humanizing profiles, Dohrmann uses the latest thinking in sports psychology-some of it learned during an intense round of mini golf with a group of professors at the annual Sports Psychology Forum-to unravel what makes sports fans so obsessive.