Edinburgh 1827. In the starkly-lit operating theatres of the city, grisly experiments are being carried out on corpses in the name of medical science. But elsewhere, there are those experimenting with more sinister forces.

Amongst the crowded, sprawling tenements of the labyrinthine Old Town, a body is found, its neck torn to pieces. Charged with investigating the murder is Adam Quire, Officer of the Edinburgh Police. The trail will lead him into the deepest reaches of the city's criminal underclass, and to the highest echelons of the filthy rich.

Soon Quire will discover that a darkness is crawling through this city of enlightenment - and no one is safe from its corruption.