The Thursday Murder Club series revolves around a group of retirees in a community that caters toward those who are in their final years, so there is a fair bit of talk about memories, nostalgia, and the passage of time. The Last Devil to Die takes things a step further than the previous three books, however, making time a central motif. The Impact of Aging, Dementia, and Mortality is a strong theme throughout, and many of the chapters featuring Stephen include discussions about the role that time plays in his experience of the world as his dementia progresses.

Many of the book’s elderly characters feel trapped in the present. They’re still alive and moving forward, but the things and people that they love are all in the past. For Stephen, the experience of living is very different. The present is foggy and confusing; the past is the only thing he can be sure about and hold on to concretely. He is no longer experiencing time as a linear progression of events, offering readers insight into other ways of seeing and considering time: “Everything I’ve done and everything I’ve been is present in the same place. But we still think the thing that has just happened, or is about to happen, we think that’s the most important thing” (242), he says.