This Poison Will Remain by Fred Vargas

In this gripping mystery, a series of seemingly unrelated deaths in Paris leads the unconventional Commissaire Adamsberg to uncover a sinister plot involving venomous spiders. As he delves deeper into the investigation, Adamsberg must navigate a web of deceit, historical grudges, and personal vendettas, all while confronting his own inner demons. With a blend of intuition and unorthodox methods, he races against time to unravel the truth and prevent further tragedy, all set against the backdrop of a city where danger lurks in the most unexpected places.