Murder, revenge, rage are the elements of many fine mysteries.

But the greatest mystery of all isn’t the stuff of daggers and detectives.

It’s love.

Who we love, why we love, who and why we no longer love.

David Gregor, longtime owner of Gregor Rare Books in downtown Langley, takes readers on that universal quest and question of romance, attraction and allurement in his book, “The Rose Tattoo: An Intimate Memoir on the Mystery of Love.”

It’s a work of non-fiction with real people and real places of South Whidbey and beyond, particularly New Orleans.

Gregor will speak about the book, the fifth he’s authored, 1-3 p.m. Sunday, Jan. 13 at Dancing Fish Vineyards in Freeland.

Gregor’s store is full of rare, first-edition books that he’s collected for decades. He turned his passion into a book-collecting business, an enterprise that once had plenty of competition in cities across the nation.

Now his trade is as unique as his books but he’s kept at it for 32 years, first in Seattle and then in Langley where he set up shop in 2004.

Asked how he ended up on Whidbey Island, he responds in the usual way, “A woman.”

“The Rose Tattoo” is a self-published book, the last of a trilogy of memoirs written by Gregor over the decades; he’s also authored a book of poetry and a reference guide for collecting rare books.

“It’s a late-life romance that explores the mystery of love and fate and the sacrifices the heart sometimes demands,” said Gregor on a recent Saturday at his small store on First Street. “That’s the elevator pitch, at least.”

Gregor is a man of words, books and a blues band called Deja Blooze. At age 68, he meets a woman of music, muffins, 100 chickens and a dog named Bella, a woman who strikes him as a “gypsy soul.” His romance with Rose Rydeen begins in the whirl of anticipation and unexpected moments he thought were gone for good.

“We had a brief, I didn’t expect it to be brief, romance,” Gregor said. “Circumstances came into play. She was a widow, I had just got out of a 10-year marriage.

“I figured I was pretty much done with love.”

Gregor’s descriptions of the heart are poetic and powerful.

His heart retreats, hidden, after the struggles of his second marriage when he encounters Rose following a concert in 2015.

“After years of thwarted affection my heart had gone numb and retreated deep in my chest.”

The sense that Rose came into his life for a reason is embedded throughout the story. It’s a force he reflects back on with candor as he recalls their many conversations and moments together.

“If we are lucky, the most influential (people) enter our life and nothing is ever the same; we are forever changed by their presence,” he writes. “They may bring us peace or guidance, uncontrollable laughter or the deepest affection; but whatever their gifts, they impart them for a reason, as if guided to us with an intent.

“They see in us, a trait or inclination that we are unaware of at the moment. And the strongest attraction is often an important quality missing in our life.”

Marian Myszkowski, director of programs at Goosefoot Community Fund, knew Rose well and read drafts of Gregor’s book.

“Rose was enigmatic,” she said, “a free spirit always up for anything social and fun. She had a complicated past, which she revealed discretely and not necessarily with accuracy.

“I don’t think any of us really knew the real Rose and that’s exactly the way she wanted it,” Myszkowski continued. “That didn’t make her any less of a good friend. With Rose you knew she loved you, she had your back, and she would fight the devil on your behalf if she had to.”

The affair ends but the lessons — and unanswered questions — provide Gregor an intimate setting to explore the universal tale of love found, love lost.

“It was beautiful. It was probably the most wonderful year of my life,” said Gregor, now 71. “All the pieces fit together.”

But as Gregor put it, “time was not our friend.”

A dose of mystical realism, with white feathers and coins encountered in strange places, breezes across the end of the tale.

“True love does exist, I learned, and not just in the young,” he writes. “Sometimes, you have to live a lifetime to truly appreciate or embrace an honest love, a love that is a gift.”