Two soldiers in Napoleon's army retreating from his disastrous campaigns in Russia are separated from their unit by a Cossack attack and stumble across an isolated Slavic town - where strange and bizarre doings are afoot! Linking up with another unit of lost French soldiers, they try to figure out where they are, only to discover that the ancient, abandoned town is deep, forbidden territory - the prison of a dark monster-god out of Slavic legend and nightmare, which seeks to use the newcomers to escape!