The Hidden Staircase :

This audiobook is narrated by an AI Voice. The Hidden Staircase is the second book in the beloved Nancy Drew Mystery Stories series. When two elderly sisters report strange happenings at their old mansion, Twin Elms, Nancy Drew is determined to uncover the truth behind the ghostly occurrences. Meanwhile, her father, Carson Drew, receives threatening messages connected to a railroad case. As Nancy investigates the eerie sounds, mysterious shadows, and unexplained events at the mansion, she discovers a secret that has been hidden for years. This classic mystery showcases Nancy's courage, intelligence, and detective skills as she faces danger head-on to solve one of her most thrilling cases yet.