A reclusive sanctuary community plays reluctant host to a dangerous criminal who appears to collude with one of their own to extend his murderous spree.
Adjusting to Rockton has taken time for Casey Butler, who left her old life for the off-the-grid Yukon town not long ago. Since moving to Rockton, Casey’s become a detective with the three-person police force and helped solve more than one unusual murder case (A Darkness Absolute, 2017 etc.). Rockton is like no other community, having been founded to assist people who need to hide out. With the help of her romantic partner and supervisor, Sheriff Eric Dalton, Casey has become aware that some of the residents are paying the community to hide from crimes they’ve committed. So maybe Casey and Eric shouldn’t be surprised when their latest supply drop includes a bound and gagged Oliver Brady, whose stepfather offers the town council $1 million to shelter him for six months. Before Eric and Casey can refuse or even learn about the nature of Oliver’s crimes, the supply helicopter has taken off, leaving Rockton with its most dangerous resident yet. Oliver is highly manipulative and determined to play residents against each other to get his own freedom. And in spite of the vigilance of Casey, Eric, and the ad hoc town militia, Oliver escapes into the woods, leaving Rockton inhabitants and residents of the surrounding area (known as "hostiles") equally unsafe until Casey and Eric can identify Oliver’s ally on the inside.
Armstrong continues to expand the highly original Rockton world, focusing this time more on the precipitating events rather than the overarching series back story.