Susan Cooper’s Greenwitch , published in 1974, is the third book in her five-book The Dark Is Rising series.
Cooper is exceptionally good at creating settings. Greenwitch is set on the coast of Cornwall, England, and as you read the author’s evocative prose, you can almost feel the mist from the sea flick at your face.
This mastery of settings carries over to her description of supernatural environments, including the protagonist’s trip to the ocean’s depths to meet with a primordial nature spirit of the deep, and another character’s unsettling encounter with a Dark One in a gypsy caravan. Her description of the underwater environs of the Greenwitch, a sort of wicker woman who’s come to life, largely works to make this supernatural being believable. Cooper’s gift for making the dreamlike tangible was, for me, the most inviting quality of Greenwitch.
She also has an ability to interweave several story threads into a well thought out narrative. And she is very successful at alternately setting a menacing tense mood, invoking nightmarish sensations, and then dispelling these the next moment as the forces of Light, and of friendship and camraderie stalwartly tackle their earnest mission – in this case, to recapture a stolen Celtic grail from the Dark Ones in order to prevent them from unleashing a reign of terror on humankind.