Hecate Goodwin, Kate to her friends, has curated the perfect life as a hedge witch, living in a secluded cottage with only a black cat for company. She spends her days foraging herbs from the Ipswich forest, gardening, and creating tinctures to sell at the apothecary she owns. Most evenings pass without her speaking to another human being, an arrangement she quite prefers.

Kate's solitude is thrown into disarray when her older sister, Miranda, reaches out and asks her to host their coven's annual Halloween gathering. The day marks the beginning of the new year for witches and is also Kate's birthday. The pressure from her coven to make the evening memorable mounts as the event draws near. To complicate things further, a handsome man from Kate's past turns up at her cottage, asking for sanctuary. It is Kate's duty as a hedge witch to honor this request, much to her dismay. Matthew Cypher is no ordinary lost soul-he's a practitioner of forbidden magic who's tricked Kate once before, and her guard is up.

As she juggles Matthew's arrival and the preparations for Halloween, Kate comes across an old tome shrouded in dark magic. She is horrified when she realizes the blood-red inscription is written in familiar handwriting: her recently deceased mother's. Afraid to even touch the dark magic her mother secretly studied, Kate can turn only to Matthew for help. Her idealized memory of her mother begins to distort, and as she and Matthew grow closer, Kate has to reevaluate whom she can really trust.

A Dark and Secret Magic is a celebration of the Halloween season and a love letter to anyone who drinks pumpkin spice in August and carries the spirit of a witch inside their heart all year long.