Possibly the only series from Paul Doherty – apart from some of The Canterbury Tales – where there is significant distance between the protagonist and the ruler of that time and place. Swinbrooke is an apothecary in Canterbury at the end of the Wars of the Roses. She is assisted by obvious love-interest Colum Murtagh and her maidservant Thomasina. There are seven books in the series, all written under the pseudonym C L Grace and, as far as I’m aware, not printed in the UK. Certainly there is no paperback versions available and there are some very expensive copies of these books available on Abebooks.
UPDATE: These are all available as reasonably priced ebooks, under Paul’s own name as author.
Pilgrims to Canterbury are being poisoned when they visit Becket’s tomb. As the murderer is known to be male, Kathryn is tasked to find the killer, as she has the expert knowledge and is known to be innocent by virtue of her gender.
Kathryn and Colum are tasked by the King to find the Eye of God, a royal relic that was lost during the Wars of the Roses. But when the thief dies in his jail cell and one of his guards dies alone on a locked roof, they realise that a cunning murderer is also looking for it.