Caitlyn is savouring autumn delights like spiced cider and toffee apples while preparing for the Samhain Festival. She's also looking forward to spending time with the dashing Lord James Fitzroy and meeting his family at last. But the festive mood is broken when a Manor guest comes to harm over an ancient grimoire that once belonged to the Widow Mags.

With the help of her toothless vampire uncle and a dash of chocolate magic, Caitlyn sets out to do some witchy sleuthing and retrieve the stolen "book of spells". She soon uncovers a bewildering assortment of suspects, including one who might be her long-lost mother in disguise! And just when she thinks things can't get more complicated, the trail leads uncomfortably close to James's sister...

As village superstitions simmer and suspicion bubbles towards her grandmother's chocolate shop, can Caitlyn solve the mystery, find the missing grimoire, and finally uncover the truth about her mother?