Fiddlers. An 87th Precinct novel

It started with the blind violinist - shot twice through the head at Point-blank range in the alley outside his dingy restaurant. It's only when the omelette lady gets shot with the same gun in the same way twenty-four hours later that the 87th Precinct really starts to sit up and take notice. But Steve Carella and the boys at the Precinct always seem to be one step behind the killer, and the death toll is rising. And why is the killer heard to introduce himself as `Chuck' before pumping two bullets into their bodies ?