“Who hurt you, once / so far beyond repair / that you would meet each overture / with curling lip?”

This quotation appears in several books of the series but becomes central to the plot of How the Light Gets In. The idea of someone sneering at the future portrays bitterness or cynicism after a deep wounding. This is what Gamache sees in the young agent who worked in Serious Crimes, or in Beauvoir who has become bitter instead of facing his trauma. Only by tracing original emotions can these characters heal.

“But Isabelle Lacoste had been in the Sûreté long enough to know how much easier it was to shoot than to talk. How much easier it was to shout than to be reasonable. How much easier it was to humiliate and demean and misuse authority than to be dignified and courteous, even to those who were themselves none of those things.”

This quote explores how cultures of evil are bred. In the showdown between Gamache and Francoeur’s leadership, the issue is not that one man is naturally good and the other naturally evil. Francoeur’s willingness to do what is easy rather than what is right is what has slowly evolved into a climate of bullying and mistreatment.

“Why do decent young men and women become bullies? Why do soldiers dream of being heroes but end up abusing prisoners and shooting civilians? Why do politicians become corrupt? Why do cops beat suspects senseless and break the laws they’re meant to protect? [...] Because everyone else does.”

This quote examines how evil grows. The novel reinforces the idea that evil, whether in an individual murderer or an abusive system, does not happen overnight, but is nurtured in over time by isolation or passive tolerance.