The Mystery of Darkmoor Hall. Ghosts of the House on the Rock

At first glance of the dead-end coastal village, Kate realized that the most boring summer of her life awaited her.
 
But within a week, before the girl, like a beast from the depths of the sea, grew Darkmoor Hall, a sinister... mansion, a home of nightmares and vengeful spirits. In the deserted halls, Kate finds not only the mystery of a missing treasure but also a strange boy: his name is Gus, and he is the sole heir of an ancient cursed lineage…
 
To unravel the mystery and save her new friend from the sad fate of his ancestors, Kate must explore every corner of the eerie house, meet the ghosts, and even descend into the bottomless darkness of the legendary dungeons.
 
Scary? Pfft! Who is even scared of ghosts! Oh, wait a minute… what was that knocking just now?..