Book ~ "The Widening Gyre" (1983) Robert B. Parker

From Goodreads ~ The adoring wife of a senatorial candidate has a smile as sweet as candy and dots her "i's" with little hearts. A blond beauty, she is the perfect mate for an ambitious politician, but she has a little problem with sex and drugs - a problem someone has managed to put on videotape.

The big boys figure a little blackmail will put her husband out of the race. Until Spenser hops on the candidate's bandwagon.

But getting back the tape of the lady's X-rated indiscretion is a nonstop express ride to trouble - trouble that is deep, wide and deadly. 

Spenser is a private detective in Boston and has been hired to head up the security detail for Congressman Meade Alexander as he runs for the Senate.  The congressman confides to Spenser that he is being blackmailed by someone who wants him to drop out of the senate race.  The congressman's wife, Ronni, drinks too much and there is a sex tape of her and a much younger man.  As Spenser investigates, he discovers who is blackmailing Alexander and sets out to stop them and get Ronni's tape back so it can't be made public.

This is the tenth in the Spenser series (there are currently 46, with the last six written by Ace Atkins after Parker's death in 2010).  I've read many over the years (and have liked the series) and have started reading them from the beginning of the series.  Though it is part of a series, for the most part it works as a stand alone.  Paul, who we first met in Autumn (the seventh in the series), is back but there isn't a lot of explanation about who he is and how he is connected to Spenser.

I liked the writing style ... I found it humorous at times.  Spenser is a tough guy with a wisecracking sense of humour.  It's written in first person perspective in Spenser's voice.  As a head's up, there is swearing.

Susan, Spenser's girlfriend of ten years, is away in Washington going to school, which creates a distance between them, literally and romantically.  They are disconnected and Spenser is out of sorts about it.  When they get together, they discuss this relationship in great detail.