Gothic horror for children. Bellairs was one of my favorite authors when I was a kid, but this is my first time reading this particular book.
The problem with reading Bellairs as an adult is that it seems unbelievable when the characters don't seem to learn anything from book to book - Johnny gets a bad feeling about something and they all brush it off every time, and yet every time this happens, something terrible follows. No lessons are learned.
But this was one of the things that was great about reading these books as a kid. It didn't matter that the characters followed the same pattern every time, because that's why you were reading the books. Something bad would happen involving wizards or witches or magicians or ghosts or curses or some other vague occult something, it would be scary, but you knew it would be okay in the end.
One thing I appreciate about Bellairs is that none of his characters are conventionally attractive in the slightest. Most of them are described in pretty unattractive terms, including the heroes of the story. Professor Childermass is "short and elderly and crabby-looking, with wildly sprouting muttonchop whiskers, gold-rimmed glasses, and a nose that looked like an overripe strawberry." Whereas Johnny is shy, nerdy, and nearly friendless; and Fergie is "a gangly, droopy-faced kid with big ears and a blunt-ended nose." No handsome heroes here. I think it made the characters more relate-able for me when I was a kid.