Blackthorn Key

London, 1665. Fourteen-year-old Christopher Rowe is apprenticed to master apothecary Benedict Blackthorn. In Blackthorn's shop, Christopher learns the delicate secrets of transforming simple ingredients into powerful medicines, potions and weapons. His beloved master guides him with a firm, steady hand - instilling him with confidence and independence that prove increasingly vital as Christopher learns of a mysterious cult preying on the most learned men in London.

Boils, blood and a burning fever - the black death has returned to London.... As the dreaded sickness spreads through the city, striking down rich and poor alike, an unknown man arrives with a miracle cure. But when an assassin threatens the life of the city's new saviour, young apothecary Christopher Rowe and his faithful friend Tom must risk their lives to untangle another dark conspiracy.