Carolyn Keene

Another exciting mystery begins for the young detective when her friends Bess and George ask her to investigate a rumor that their wealthy great-granduncle, Asa Sidney, is virtually a prisoner in his own mansion. But solving the mystery and befriending Carol Wipple, the sixteen-year-old foster daughter of the …

The Sky Phantom is the fifty-third volume in the Nancy Drew Mystery Stories series. It was first published in 1976 under the pseudonym Carolyn Keene. The actual author was ghostwriter Harriet Stratemeyer Adams.