On February 18, 2001, NASCAR superstar Dale Earnhardt Sr. was killed in a crash on the Daytona 500 racing track in front of 250,000 people. How could this fearsome and fearless driver, driving a car he knew, on a track he knew, die in an accident that looked minor by NASCAR standards? Investigators wanted to know how a seemingly mild crash killed Dale Earnhardt. The ensuing investigation revealed a shocking case file that rocked NASCAR to its core.