William “Bill” Herbert was the enigmatic writer, producer, director, and editor of the 1973 cult horror film Warlock Moon. Working under the pseudonym John Sykes, he crafted the low-budget psychedelic thriller on a $25,000 shoestring, filming in abandoned California locations with a cast of local theater actors. He even appeared uncredited as a corpse. After a brief local premiere in Livermore, Herbert vanished from filmmaking. No interviews, no follow-ups, no photographs. Rumors persist that he was an early alias of TV director Gregory Hoblit, fueled by actor Joe Spano’s cryptic comments, but no proof exists. A true one-and-done auteur, Herbert left behind only one weird, unforgettable gem—and a mystery that outlives the moonlit spa.