In the melting pot of 1890s London, Sergeant Cork works for Scotland Yard's newly formed Criminal Investigation Department, enthusiastically employing the pioneering techniques of the new science of forensics to tackle crimes born of poverty and deprivation, passion, vengeance and greed. Ably assisted by youthful detective Bob Marriott, Cork is astute, years ahead of his time, and knows that even the most convincing evidence can all too often deceive.