His mild manner seems at odds with the lurid violence of crime novels. In “Death Notice,” the killer of two police academy cadets in a gruesome bombing resurfaces after 18 years, this time orchestrating the murder of a revered police sergeant whose failure to solve the original case haunted his career.

Then, as now, the killer fashions himself as an avenger, bringing justice to those whose crimes have gone unpunished. The killer calls himself Eumenides after the third of the Oresteia ancient Greek tragedies by Aeschylus and warns each of his victims in notes drawn with exquisite Chinese calligraphy, luring the police into a diabolical game. The new killing spree revives a special police task force that had been shelved for reasons that, to explain fully here, would amount to a spoiler.

Of course, censorship shapes crime writing here, which to some can make the genre seem relatively wan. A Yi, who was a police officer in Jiangxi Province before writing thrillers, said in an interview that the crime novel might have exhausted its potential in China. “Crime novels still do very well,” he said, “but for the writers, creating these stories is getting harder and harder.”

Mr. Zhou acknowledged that the censors had posed problems, forcing him to make changes in his books, but he said that novels tend to get more leeway than movies or content online, which the government polices with greater zeal because that is where more Chinese are spending their time. The investigation at the heart of “Death Notice” does hinge on questions of police corruption and the privileges the wealthy in China enjoy — all of which are experiences Chinese readers can relate to.