The madness of crowds / Louise Penny.

When Inspector Gamache is asked to provide crowd control at a statistics lecture given at the Universite de l'Estrie, he is dubious. What lecture might be so contentious that it would require the Surete du Quebec to supervise it? But following the pandemic, dangerous ideas about who deserves to live in order for society to function are rapidly gaining popularity, fuelled by the research of the eminent Professor Abigail Robinson. Yet for every person seduced by her theories is another one who is horrified by them. When a murder is committed days after someone tried to shoot the professor on stage, it's clear that someone in Three Pines is prepared to do anything to stop her. To uncover the truth, Gamache must put his own feelings about the divisive Professor to one side. But with a vision of humanity itself at stake, the line separating good and evil can blur just as quickly as the one between reason and madness - especially when the clues lead unexpectedly close to home.