No one knew much about him. He was a black man with close-cropped hair who looked to be in his 40s. He had a high school class ring. He had been at the convention center for four days, no different from thousands of others. Friday night, he lost it. While others tried to sleep on the sweltering sidewalk around him, he began to mumble to himself, kicking aside piles of trash. He yelled something about his missing wife. Just before midnight, a police car screamed down Convention Center Drive, and from there, the stories diverge. Some said he just ended...