Delia Graves and the Order of Merlin revolves around the title character Delia, a coroner in a small town where mysterious and unexplainable crimes are on the rise. Fearing for her safety her estranged mother shows up after 20 years to reveal that Delia had a spell cast on her at birth that will allow her to access Merlin's powers and that she will need to train to protect the town, and maybe even the world.