The Blackthorn Key by Kevin Sands
Here you will find a fine historical thriller, with lots of bang for your buck.
Christopher Rowe is apprenticed to the alchemist Benedict Blackthorn, in the London of the 1660s. Gifted and ever eager to learn, he is sorely tested when a series of murders happen in the streets near St Paul's Cathedral. The Cult of the Archangel is thought to be behind the murder and mutilation. But soon the finger of guilt is pointing in an altogether more perilous direction. Evading the authorities and told to trust no one, Christopher must prove his innocence, bring the perpetrators to justice and tame the wrath of God.
Sands writes with an evident love of Restoration London. He conjures a satisfying plot, with a marvellous balance of political intrigue and puzzle solving — all this in a time before the days of the periodic table, when magic, science and religion were inseparable. It is an indictment of how the thirst for knowledge was so often corrupted by man's desire for power and warmongering.
With a hefty dose of mysterious, alchemy, chemistry and code breaking, this is a welcome addition to a rather neglected canon of robust historical thriller that will remind some of the works of Leon Garfield and Robert Welch. To fill the gap between this fine novel and its sequel, you would do well to consider Coram Boy, King of Shadows, Oranges and Murder, Raiders Tide, The Raging Quiet or (for another more contemporary fix) Gifted/Pariah.