Once more into the Arctic for Francis McNally—a now-semi-retired private investigator—this time to honor the passing of a friend, Auguste Demarais, who had worked some magic (or miracles) for Mac and to whom the PI says plainly, "I owe you everything."
This time around, he convinces his wife Linnie to accompany him and remain in Toronto with a friend while Mac continues north, sees to Demarais's remembrance, and then rejoins her for a short vacation. When he arrives at Baker Lake, however, he finds the town in turmoil: a murder remains unsolved, a popular schoolteacher has disappeared, and an aggressive and bigoted nationalism has sprung up in the predominantly Inuit community.
Mac may be cutting back, but he finds a connecting thread quickly. Under ordinary circumstances, he would sign on and get to work, but his wife is waiting for him, and the events in Baker Lake are being supplanted by fear of some new virus that, according to scientists, will kill millions and shut down the world.
Amidst all this, McNally picks up some quick history lessons, learning of the horrors inherent in the residential schools and realizing that bigotry and racism, disguised as a political movement, know no borders. But he has to learn fast; after all, there's this virus....