John Connolly has written more than a dozen novels featuring Portland private investigator Charlie Parker, starting with “Every Dead Thing” in 1999. So it wouldn’t be surprising if the Irish author felt a desire to bump off his signature character after such a long time, just as Sir Arthur Conan Doyle gave in to the temptation of chucking Sherlock Holmes over the Reichenbach Falls.

But having taken Parker beyond the brink of death and back in the preceding volume, “The Wolf in Winter,” Connolly reveals in his new novel that what he wants to accomplish is the revitalization of his haunted detective. The climactic, all-but-deadly shotgun blast in the previous installment proves physically and spiritually transformative in “A Song of Shadows.”

Parker arrives in the quiet, fictional Maine seaside town of Boreas with the intention of recuperating from grievous injuries that have left him weak, stiff, minus one kidney and prone to debilitating headaches. But even as he settles into a rental unit that suits his particular needs – and the demanding safety standards of his friends/guardians/sometimes-partners-in-crime Louis and Angel – Parker finds himself surrounded by terrible reminders of mortality. The body of a presumed suicide washes up on a local beach. Later, four members of family in a nearby town are massacred in their home, seemingly by the oldest child, a misunderstood teenage boy who subsequently disappears.

Amid this chaos, Parker initiates a tentative friendship with a youngish widow, Ruth Winter, and her daughter Amanda. Amanda suffers from chronic fatigue syndrome, which keeps her out of school a lot. Ruth is tense and distracted, and Parker suspects that something more than simple maternal concern is bothering her. Indeed, Ruth has attracted the attention of something evil, and Parker will be called upon to risk his life to protect her and her daughter.

Connolly is adept at devising truly despicable villains, and he does not disappoint in “A Song of Shadows.” From the moment he is introduced tormenting a bar owner from whom he needs information, a monster in human form named Steiger makes an indelible impression. But there are other, better-hidden antagonists lurking in the background. Given the swastika-adorned cover of “A Song of Shadows,” no spoiler alert is necessary regarding the book’s inclusion of Nazis. While the oldest of the former concentration camp officers are on their last legs, there remain younger loyalists ready to commit murder.

The Charlie Parker books are notable in the ways in which they blend the traditions of the private-eye novel with the anything-goes urgency of the supernatural thriller. Ever since his wife and daughter were murdered in “Every Dead Thing,” Parker has operated on a different psychic wavelength than the rest of humanity. Connolly doesn’t always find the right balance, sometimes letting the occult overwhelm the narrative, when a little more conventional crime-solving would be more welcome. But “A Song of Shadow” walks the line gracefully, maintaining a strong connection to the real world while offering glimpses of a dark and horrific universe.

Some of the best scenes in the novel involve Parker and his surviving daughter, Sam. Although it breaks his heart, Parker can’t help but see that she, too, has mysterious powers, and he dreads what her otherworldly gifts might portend. Her ability to communicate with her dead half-sister Jennifer is especially troubling.

Connolly has stretched his ambitions with each book, and Parker has definitely evolved since his introduction more than a decade and a half ago. The detective’s friends are able to see the changes in him and worry about them. Connolly writes, “Yes, thought Angel, Louis was right: He is different. He has a certainty to him that was not there before. He should be dead, yet he is more alive, and more dangerous than ever.”

While Connolly’s readers can surely savor the many dark pleasures of “A Song of Shadows,” most will finish it wanting more. Not that the author has held anything back, but because the transformed Charlie Parker is so compelling. He is clearly destined for a ferocious showdown in the next novel, reportedly and tantalizingly titled “A Time of Torment.”

Berkeley writer Michael Berry is a Portsmouth, New Hampshire, native who has contributed to Salon, the San Francisco Chronicle, New Hampshire Magazine, the Los Angeles Review of Books and many other publications. He can be contacted at:

mikeberry@mindspring.com

Twitter: mlberry