“Edge of Redemption” is an interesting mystery that pits lead detective Cole Sullivan of the Maine Homicide Investigation Unit (HIU) against a psychopathic killer who seems unstoppable. Murdering mostly for pleasure, the killer’s random strikes stymie law enforcement.

As weeks go by and victim numbers soar, the press turns critical of Sullivan. The Maine governor — concerned because citizens are afraid for their lives — replaces him as HIU’s head with the overly ambitious sheriff of Cumberland County.

But killings continue, and it’s only when the governor reappoints Sullivan that progress resumes on the case. Author Russell Warnberg doesn’t reveal the killer’s identity until the final chapter, but some readers will guess the culprit earlier in the book.

Overall, “Edge of Redemption” is a good, suspenseful read with a commendably imaginative plot. But Warnberg’s first novel has drawbacks, the worst of which is the overuse of cliches.

Police in the homicide unit can’t relax because “they all had the case rattling around in the back of their heads” Cruisers “turn on a dime.” And “danger reared its ugly head” for a potential victim of the psychopath. My concentration broke up when I read that three policemen “flew out of the office” upon learning of another murder.

In fairness, Warnberg’s overuse of trite expressions won’t bother all readers. And, when it comes to setting up a scene, he does it well.

Consider the first page of “Redemption”: An elderly farmer steps out on the porch of his rural home early one morning, smiling as he looks up and remembers how his children used to play beyond an old maple. At that precise moment, writes the author, “A small-caliber bullet pierced his jacket He barely felt it, but it got his attention as he fell to his knees. Looking up for the last time, he fell face down on the porch.”

Warnberg, who lives in Windham, spent many years teaching history, English and other subjects at public and private schools in Maine and Minnesota. He holds a master’s degree in education from the University of Maine, and an associate’s degree from the University of Minnesota. He grew up in Minnesota, and served in the U.S. Navy before moving to Maine.

“Edge of Redemption” is a big- scope mystery with characters ranging from the Maine governor to teenagers in rural towns. The action ramps up in a major way when the super-psychopath aims his rifle at the officers in the HIU.

Yes, there are cliches, and you’ll probably find Warnberg’s female characters more angelic than real. But ultimately, “Redemption” is a well-crafted mystery pitting law enforcement against a loathsome killer. 

Lloyd Ferriss is a freelance writer and photographer who lives in Richmond.