This is the forty-fourth book in the Spenser series and the fifth to be written by Ace Atkins in the wake of Robert B. Parker's death. As any number of other reviewers have noted, Atkins has pretty effectively restored the series to its glory years, and with this many books under his belt, he is beginning to make the series his own.
With Atkins at the helm, Spenser's universe is slowly changing. New characters are appearing, and the man himself is now moving into the modern day, particularly with regard to technology. Spenser long ago stopped aging somewhere in his early fifties, which is a very good thing. When the detective first appeared in The Godwulf Manuscript in 1973, he was a veteran of the Korean War. He would thus now be somewhere in his middle eighties and might have some difficulty beating up large, well-muscled bad guys who are only in their twenties. At one point in this novel, Spenser notes that he once served in the Army. He says that he didn't do much in the Army, but Atkins gives us no hint as to when or where Parker might have served, and in this case has clearly learned a valuable lesson from his predecessor.
As this book opens, Spenser is approached by a Boston firefighter named Jack McGee. A year earlier, an abandoned Catholic church in Boston's South End went up in an inferno. Three firefighters who were friends of McGee's died fighting the blaze. McGee insists that the fire was deliberately set, although the arson investigators have been unable to determine a cause for the fire. McGee also believes that the fire may well have been connected to a series of arsons that have plagued the city in the past year.
McGee believes that the fire and police departments have given up too easily in attempting to solve the fire at the church and he wants Spenser to look into it. Spenser has no training as an arson investigator and one might well wonder how he could possibly turn up evidence that has eluded the seasoned arson and homicide investigators. McGee believes, though, that Spenser has connections in Boston's underworld that aren't available to the police and fire department investigators and that by probing these sources, Spenser might find the guilty party or parties.
It is, frankly, a pretty thin excuse upon which to build a plot, but who really cares? The story is off and running and it's great to see Spenser back in action. From the reader's perspective, there is no real mystery about who's responsible for the fires. The bad guys are revealed even before the first chapter begins, and the tension depends on the rising stakes, for the fire department, for the city of Boston, and for Spenser personally, as the fires rage out of control. It's another very good read and further proof of the fact that the Parker estate knew exactly what it was doing when it entrusted this iconic series to Ace Atkins.