Wychwood (Book 2 of 2) by George Mann

After losing her job and her partner in one fell swoop, journalist Elspeth Reeves is back in her mother’s house in the sleepy village of Wilsby-under-Wychwood, wondering where it all went wrong. Then a body is found in the neighbouring Wychwoods: a woman ritually slaughtered, with cryptic symbols scattered around her corpse. Elspeth recognizes these from a local myth of the Carrion King, a Saxon magician who once held a malevolent court deep in the forest. As more murders follow, Elspeth joins her childhood friend DS Peter Shaw to investigate, and the two discover sinister village secrets harking back decades.