From the introduction:
The chaotic River Kingdom of Daggermark maintains a semblance of stability via a common understanding among its residents: those who draw their neighbor’s ire often end up dead. Daggermark’s Assassins’ Guild and Poisoners’ Guild hold considerable sway in the unruly city-state, sharing power with the local military. New members of the Assassin’s Guild receive local contracts as part of their training, and any citizen can hire a student assassin once per year at a reasonable price. Only members of the military are exempt from these trainee contracts, meaning those who seek security and social advancement often enlist in the army. This system has kept the peace for years, but a cabal of Assassin’s Guild defectors called the Ghostknives sees the military exemption as a loophole it can use to overthrow the Guild and seize control of the city. By quietly eliminating army officers and replacing them with coconspirators, the Ghostknives could set the stage for a bloody coup.