I found this tale remarkable, full of magic, captivating. Murdoch's beautiful prose provides the spiritual warmth of a protective covering: harbouring innate Good, the essence of human relationships, from contaminating Evil, hiding in the shadows of conscious existence. Although I am a disbeliever of all things supernatural I found the religious precepts highly entertaining and intellectually stimulating (I would have benefited from a better understanding of Buddhism and Judaism). The characters (as in many Murdoch novels) are superbly constructed, engaging, complex personalities, their lives described with sublime humanity. The plot is engrossing, surreal on occasions, funny, high in anticipation and mystery. The story provides many fascinating insights into the nature of madness, religious obsession, the uniqueness of mutual love. Highlights include Father Damien's correspondence with Bellamy, the pet dog's trek across London (and its far reaching consequences), Moy's collection of stones, Mir's green umbrella, anything to do with Lucas (particularly his advice to Sefton). As suggested by the title, knowledge of the fourteenth century Middle English poem "Sir Gawain and the Green Knight" may be useful. The book was a delight to read and another example of Murdoch's exceptional talent.