The tension that was lacking from McBains last installment (Lady Killer) is evident in full force with Killer's Wedge. The widow of a recently deceased convict enters the detective's division of the 87th with a gun and a bottle allegedly filled with nitroglycerin, and proceeds to take the station hostage as she awaits the return of Steve Carella, the man she blames for her husbands death.
Lieutenant Byrnes, Meyer, Hawes, Kling, Brown, and Willis find themselves at the mercy of a vengeance lusting woman with a homemade bomb, unable to communicate with one another on how to gain control of the situation. Much of their story involves internal monologue as the bulls debate thrier options while second-guessing the others. Several attempts to get help or subdue the widow of various levels of ingenuity are undertaken as emotions run high. Interestingly enough, the main focus of the story, Carella, spends the length of the book investigating the supposed suicide of a rich industrialist while the usual cast of background characters spend the majority of their time in the spotlight as the try to diffuse the situation before Carella walks into his own execution. This gives the reader a welcome chance to spend more time with the other vivid and often neglected characters populating the 87th
The only real personal story involved is the revelation at the beginning of the book that Teddy is pregnant. Her appearance at the station to meet Carrella for a night of celebration manages to increase the tension.
The title of the book has the same dual meaning as earlier novels like Con Man, as the titular "wedge" refers not only to the the distance created between Byrnes and his command by the vengeful woman in black, but also a piece of wood the weighs heavily in the solution of Carella's locked room mystery. This is not the only parallel between the two stories, as Carella's obsessive investigation into the "locked room mystery" of how a man found hanging in a room locked from the inside could have been murdered mirrors the reality of his fellow bulls finding themselves locked in a room with a murderer.
On a side note, McBain tips his hat to a fellow mystery writer when he has Carella, pondering the impossibility of his locked room suicide/murder dillemma, wonder if he should simply John Dickson Carr for an answer.
I have read all of McBain's 87th Presinct books. This is one of the early ones---still a good one, though.