A Streak of Light Hardcover – January 1, 1976 by Richard Lockridge 
Book 9 of 10: The Nathan Shapiro Mysteries
 
From the jacket: Roger Claye, rancorous right-wing political columnist for the New York Sentinel, made his reputation by sounding off about the breakdown of law and order all around him. They broke down, unfortunately for Mr. Claye, early one morning in his own office, when someone put a bullet through his head. It's definitely a front-page murder case, and Lieutenant Nathan Shapiro and Detective Tony Cook of Homicide, Manhattan South, hardly have a chance to begin their investigation before someone again turns the Sentinel's offices into a shooting gallery. Who's behind it? A left-wing terrorist group? The curiously dry-eyed, philandering widow of the late Mr. Claye? Or is the culprit a disgruntled employee of the newspaper? This is one of Shapiro and Cook's toughest cases, and one they solve brilliantly with a clue as simple as a streak of light.
 
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