After completing The Kiesha'ra Series, Atwater-Rhodes released her tenth novel, "Persistence of Memory" on December 9, 2008. She later revealed that her first four novels and "Persistence of Memory" are part of the Den of Shadows. To mark this, her first four novels, "In the Forests of the Night", "Demon in My View", "Shattered Mirror" and "Midnight Predator" respectively, were re-issued with new cover art for the Den of Shadows and the same four novels were released in an omnibus called "The Den of Shadows Quartet" on August 11, 2009.