John Campbell, the Shreveport-born slide guitarist and self-professed hoodoo man, hated going to sleep, for fear he would not wake up.

"He didn't like the day to end," remembers his wife, Dolly Campbell. "He fought sleep all the time."

In the early morning hours of June 13, his fears were realized: Campbell, 41, died in his sleep at his New York City apartment, reportedly due to heart failure.

The John Campbell story is an intriguing one, right up to its abrupt conclusion, and beyond...