The Gray Hunter's Revenge

In the 17th book of the Hardy Boys Adventures series, Frank and Joe Hardy are drawn into a mysterious case involving a tragic death, strange happenings, and a suspected haunted house. As they investigate the disappearance of valuables and the odd events at Nathan Foxwood’s estate, they begin to question whether supernatural forces are at play or if there's a rational explanation behind the mystery. The brothers must uncover the truth behind the strange occurrences to solve the case.