The Foxglove King by Hannah Whitten

At thirteen Lore was found on the streets and taken in by a gang of poison-dealers, helping spy on their rivals. So far she's much like any other abandoned child on the streets of the city, but she also has a hidden, untapped ability to work highly illegal 'death magic'. She keeps this talent closely hidden, until one day a seemingly everyday drug drop goes wrong and she attracts the attention of the Presque Mort, the king's warrior monks. Arrested, she expects death or banishment but King August has a use for her - to uncover who or what has been killing the inhabitants of scattered villages, and to spy on his son, Bastian. Thus, Lore finds herself thrown into the strange (to her) world of the court, with its protocol and parties, where no one can be taken at face value or trusted - least of all, perhaps, Prince Bastian, and the Presque Mort monk Gabriel instructed to keep an eye on Lore and initiate her into the ways of the Court.

Having read Hannah Whitten's For the Throne, I'd rather expected something similar - a fairytale setting in which the foxglove king would be a flower-surrounded fairy - but instead the setting is more urban (though still that never, never time of fantasy novels) and the foxgloves are not the beautiful purple flowers but the drug derived from them.

The story is just as compelling though. There are so many things to love about this book. The world building is brilliant -  both the overall religious set up of quarreling gods and sainted kings, with a magic system which derives its power from death (mortem) and life (spiritum),  and the in detail political divide between the rich and the poor, where the poison which brings relief is freely available to the rich, but only obtained illicitly by the poor. The plot is a twisty intrigue-filled thriller, with Lore uncertain whose version of events to believe, and to further muddy the waters there's a love triangle.thrown in, as Lore finds herself torn between stiff, repressed Gabriel, and idle, pleasure-loving Bastian.

I really enjoyed it and look forward to book 2 of the series.