Move over, Lerner and Lowe. Stephen King and John Mellencamp, theater rookies, have teamed up for “Ghost Brothers of Darkland County,” debuting in April or May of 2009 at the Alliance Theatre in Atlanta. Set in 1957, “Ghost Brothers” centers on a simmering 40-year-old legend about the strange deaths of two brothers and a beautiful young girl in the fictional town of Lake Belle Reve, Miss. The idea for the show came from a story Mellencamp heard as a youth in his hometown of Seymour, Ind. Peter Askin (“Hedwig and the Angry Inch”) will direct.