When Spenser is protecting someone, he gets shot. He then learns that there a chance that he might lose the use of his injured arm. So he has therapy while waiting for the surgery that could fix it. And at the same time, the man he was protecting, not wanting to let anyone else get hurt is willing to give to the people who were trying to kill him.
A vigilante named Sammy writes a book and angers the Boston mob. Turns out the Feds, the mob and Hawk all want Sammy dead for different reasons. William H Macy makes an early cameo and Spenser must tie all the loose ends together.
Spenser is hired to protect ex-undercover cop, Nick Cavanaugh. As Judge Emmett Cavanaugh tries to make a deal with Crime Boss Gus Harley to safeguard his son and get Cavanaugh's son, Kevin, released from prison, Cavanaugh's other son, Georgie, tries to work his own angle. Along the way, Spenser's ex-girlfriend, Susan, returns from San Francisco. Double dealing and family intrigue lead to a terminal shootout.
Spenser and Hawk are on opposite sides of a case when a hot shot young black teenager tries to be a young "Hawk" - his idol. He is a witness to a double murder. Hawk wants to send him away. Spenser wants him to do his duty. Fireworks erupt.
Lt Quirk confronts his own mortality following being outrun by a murder suspect and receiving death threats. While Quirk recovers from a heart attack and contemplates retiring, Spenser and Hawk track down who is making the death threats and shooting at the Lt.
Spenser breaks up a domestic dispute, and gets charged with assault. Meanwhile, Susan is sexually harassed by her thesis adviser and turns to Hawk. Shortly thereafter an attempt is made on Susan's life. As Spenser deals with the assault charge, he and Hawk also track down Susan's assailant, while Susan must defend her program of study before the same board looking into the harassment charges she filed against her adviser.
Spenser takes Susan to Plymouth for Thanksgiving and runs into an old Army buddy whose down on his luck. When his friend, Mike Kaminsky, is accused of murdering the young wife of an elderly philanthropist, Spenser tries to prove him innocent. As Susan looks after the Kaminsky family, Spenser and Hawk search out the shifty background of the murder victim, and deal with the controversy conscious step-son. Attempts on Spenser's life ultimately lead he and Hawk to the those responsible.
A hit man kills one of Spenser's friends in a shoot out on the street. Spenser must defend himself after he shoots a kid while attempting to follow the hit man and is accused by a witness of being reckless. While Spenser struggles with the consequences of his actions, and figures out what the real situation was with the kid he shot, he and Hawk track down the hit man for a final showdown.