In the midst of the fighting, two Russian soldiers seek refuge in the crypt of a German church. There, clutched in the hands of a skeleton priest, they find The Shepherd; a priceless icon thought to have been destroyed long ago. When news of its discovery reaches Moscow, Stalin calls upon his most trusted investigator, Inspector Pekkala, once a favorite of Tsar and known to all of Russia as The Emerald Eye.

To unravel the secret of the icon's past, Pekkala traces its last known whereabouts to a band of self-mutilating radicals known as The Skoptsy, who were hunted to extinction years by the Bolshevik Secret Police. Or so it was believed. As Pekkala soon learns, the last survivors of this brutal sect have clung to life in the shadowy forests of Siberia. With the reappearance of the icon, they have returned to claim the treasure they say belongs to them alone, bringing with them a new and terrible weapon to unleash upon the Russian people. Unless the Emerald Eye can stop them.