In the year 1543 of King Henry VIII's turbulent reign, the daughter of a notorious alchemist finds herself suspected of cold-blooded murder...

Bianca Goddard employs her knowledge of herbs and medicinal plants to concoct remedies for the disease-riddled poor in London's squalid Southwark slum. But when her friend Jolyn comes to her complaining of severe stomach pains, Bianca's prescription seems to kill her on the spot. Recovering from her shock, Bianca suspects Jolyn may have been poisoned before coming to her--but the local constable is not so easily convinced.

To clear her name and keep her neck free of the gallows, Bianca must apply her knowledge of the healing arts to deduce exactly how her friend was murdered and by whom--before she herself falls victim to a similar fate...