As Halloween descends upon the Scottish seaside town of Nairn, reluctant sleuth and knitting enthusiast Paislee Shaw finds herself investigating how an ancient ghost inspired a modern murder . . .

While Paislee will be celebrating All Hallow's Eve by handing out candy to the trick or treaters at her Cashmere Crush sweater shop, her teenage son Brody seems to have given up the ghost. Uninterested in donning a superhero or monster costume, he's just going to attend a party with his friends at the ice rink.

But Brody got swept up in the spirit of the season after all. Dared by the older kids, he went to the supposedly haunted Rait Ruins to capture video of a vengeful ghost. The local legend of the Rait Wraith has been passed down for generations—and still gives Paislee the creeps. While no specter actually roams the grounds, the lifeless body of university student Ailis Barclay is discovered there.

Ailis was at the ruins dressed as the ghost to prank Brody, only something went wrong. With her son traumatized and deemed a suspect, it's up to Paislee to string together whether Ailis was a victim of the real Wraith of Rait Ruins—or of someone dangerous among the living . . .