Lost boy, lost girl. Peter Straub. 2003.

A woman kills herself for no apparent reason. A week later, her teenage son disappears. The vanished boy’s uncle, Tim Underhill, is compelled to return to his home town of Millhaven to discover what he can.

A madman known as the Sherman Park Killer has been haunting the neighbourhood, but Underhill believes that Mark’s obsession with a local abandoned house is at the root of his disappearance. He fears that in peeling back the house’s hideous secrets, Mark came across its last and greatest secret - a lost girl, one who has coaxed Mark deeper and deeper into her mysterious domain, where he must encounter a fearsome adversary.