This is the premise of Susanna Gregory’s The Westminster Poisoner, and if you're at all familiar with her highly reliable brand of historical crime fiction, you will know that you are in for something of a treat. As Chaloner begins to unpeel the layers of deception around the killings -- and finds that there is much interest in his employer’s background -- he is plunged into a morass of corruption and double-dealing in which no one can be trusted.
As always with Gregory, the impeccable plotting is matched by the vivid conjuring up of a long past year: 1663 is brought to life for the reader in all its splendid and squalid aspects, with Chaloner the perfect guide through this (at times) surrealistic universe, often very like the present day (the political corruption might suggest a few modern-day parallels), but also massively different from the Britain we know. Even if you feel you have no taste for historical crime fiction, it might be in your interest to overcome your prejudices in this case. --Barry Forshaw