Is there no explanation of the mystery of The Haunted Hotel?

Is The Haunted Hotel the tale of a haunting -- or the tale of a crime? The ghost of Lord Montberry haunts the Palace Hotel in Venice --- or does it?

Montberry's beautiful-yet-terrifying wife, the Countess Narona, and her erstwhile brother

are the center of the terror that fills the Palace Hotel. Are there malefactions at the root of the haunting -- or is there something darker, something much more unknowable at work?

(Goodreads)