Brian Histand, a 25-year-old nationally renowned BMX rider, was last seen wandering in an alfalfa field on the southern edge of Phoenix, Ariz. Police respond to reports of a naked man in the fields but determine that Histand doesn't pose an imminent threat to himself or others. Family and friends fear for his safety in the harsh Phoenix heat and, as they search, they learn that he's exhibited disconcerting behavior over the last few days. Histand never wore a helmet while biking despite his fondness for stunts and jumps. Could concussions from his risky bike moves have led to a dangerous state of confusion?