McDermid wrote Killing the Shadows after a holiday trip to Toledo in Spain. What a fantastic place to have a serial killer operating, she thought, staring at the honey-coloured medieval buildings nestled atop a mammoth chunk of rock towering over the Tagus River and thinking of Toledo's bloody history dating back through the Civil War and the Inquisition all the way to Roman times. She dumped the body of a young tour guide in La Degollada, a gorge named after a gypsy woman who had been found there centuries earlier with her throat cut. And she hung the sodomized corpse of an American graduate student from the manacles adorning the faade of the monastery church of San Juan de los Reyes.