When a series of gruesome cult killings take place near the British Museum, DCI Harker and his assistant DS Critchley are called to London to solve the case. 

Middle class satanists, dusty old bookshops, a labyrinth under the museum, a frantic car chase and wry, cutting humor all combine in this love letter to classic British detective television series. 

Written by newcomer Roger Gibson and illustrated by the adept Vince Danks, Harker takes police investigation to a true heart of darkness.