Ever since the birth of modern roller derby in the 1930s, this dangerous and dynamic sport has lit up the souls of millions of fans worldwide. Players risk life and limb in dazzling displays of daring, skill and strength, and audiences shower them with enthusiastic adulation and affection. During the 1970s, roller derby became a sports entertainment phenomenon in North America. Matches were broadcast live on television and banked-track arenas were packed out with crowds cheering wildly for their favorite teams. In the 1980s, a deadly virus threatened to...