In Michael Koryta’s exciting “Rise the Dark,” private investigator Mark Novak sets out to find his wife’s killer and winds up confronting a lunatic who is plotting to take over the United States.

At the outset, Novak’s search takes him to a Florida town that’s home to spiritualists who claim to talk to the dead. He meets an attractive woman named Janell who isn’t who she claims to be. She very nearly kills him and she’ll kill others before the story is over, often by deftly wielding a knife. But she is not his wife’s murderer.

So Novak’s search continues, taking him to Montana, where he grew up and is reluctantly reunited with family members who are given to drugs and petty crime and are allergic to honest work. His mother, in fact, will prove to be in cahoots with the novel’s No. 1 ­villain.

"Rise the Dark" by Michael Koryta (Little, Brown)

His name is Eli Pate and he is obsessed with a grandiose scheme to topple the U.S. government by sabotaging the electrical grid system. To mess with the system’s huge transmission towers is exceedingly dangerous, but Pate plans to disable scores of them. Then, with the country abruptly in the dark and without power, he’s counting on well-armed ­anti-government militias to enforce his takeover. “When darkness fell, chaos would reign, and the man who controlled the chaos? His ascent to leadership was natural order.” So goes his fantasy.

Pate, although possibly mad, is not stupid. He speaks nine languages and worships the pioneer electrical innovator Nikola Tesla, whose grievances have somehow inspired him. In furtherance of his scheme, Pate has kidnapped the wife of a skilled grid-systems engineer to force the man to help him. This engineer had quit performing high-voltage repairs atop “massive transmission towers with their nearly a million volts” after an accident killed his brother-in-law. He vividly remembers the result: “The electricity cooked you in your own blood, leaving nothing but a blackened, shriveled shell behind.” But now he must climb again to save his wife.

Along the way, Novak meets a fellow investigator he can’t ignore, even if he has avoided women in the two years since his wife’s death. Her name is Lynn and she’s blessed with “high cheekbones, a delicate jaw, and eyes that seemed to be in on a joke that the rest of the world hadn’t gotten yet.” But Lynn has her secrets, and he has his problems, although he keeps telling himself that you can’t be unfaithful to a dead person. The romance is a troubled one.

The author Michael Koryta (Jonathan Mehring)

Koryta nicely captures the beauties of Montana: “They were on a high plateau rimmed by mountains, peaks looming in all directions,” he writes. “The Montana sky felt older than time and endless as space itself. It was a humbling sky.”

In the novel’s conclusion, Mark does battle with the thug who killed his wife and other well-armed men as he tries to free hostages being held in Pate’s mountain fortress. Pate, meanwhile, has his electrical engineer hostage 100 feet up a tower, trying to bring darkness to the West. Does this madman succeed in dousing the lights all over the United States? The outcome is complex and fascinating.

“Rise the Dark” is Koryta’s 12th novel. A former private investigator and reporter, Koryta has won prizes and scored bestsellers, but he is not as well known as he should be. This book arrived with high praise from several stars of the genre — “A master,” says Stephen King; “Outstanding,” adds Lee Child — and they’re right. “Rise the Dark” is both first-rate entertainment and an unusually interesting thriller in terms of its characters, its plot and the ideas it explores, which include the electrical grid, Tesla’s history, spiritualism and the nation’s possible vulnerability to a right-wing takeover.

This is Koryta’s second Mark Novak novel after last year’s “Last Words,” and its ending suggests a third one. For one thing, Novak has finally learned from his mother who his father is, and there probably will be surprises if father and son meet. Moreover, although most of the troublemakers in “Rise the Dark” will do no more harm, one remains at large. That’s Janell, the comely psychopath who’s so handy with a knife. She lusts for revenge on Novak, and the feeling is mutual. A rematch should be fun.

Patrick Anderson regularly reviews mysteries and thrillers for The Washington Post.

rISE THE DARK

By Michael Koryta

Little, Brown. 400 pages. $26