“Once upon a time” is probably the most seductive phrase in the language of books. Add a forest, a witch, a giant and a princess, and children are enchanted beyond any reasonable doubt. No need to know the story’s setting (it’s a kingdom!) or the king’s reasons for beheading his daughter’s suitors one by one (they gave the wrong answer!).

Even adult readers still warm to the tall tale, the fable and the fairy tale. Maybe that’s the reason I was already thoroughly sucked into the spooky yet oh-so-familiar world of “The Kings and Queens of Roam” by the time its narrator explained that “it’s impossible to say exactly where Roam is,” and that it was “shadowed by dark green forests full of bears and wild dogs.” It’s the fifth novel from Alabama native Daniel Wallace, best known for “Big Fish,” a book that summoned up a magical realism unique to the South, drawn from the American storytelling tradition as well as Greek myth, fairy tales, folktales and legend.

Wallace followed up with “Ray in Reverse,” “The Watermelon King” and “Mr. Sebastian and the Negro Magician.” All share his signature use of fantasy and real life to examine the importance and consequence of story – both those we tell others and the ones we tell ourselves.

“Kings and Queens of Roam” returns to those consequences in the tale of a 100-year-old town inhabited by a handful of eccentric natives and the ghosts of everyone who ever lived there. Founded by greedy industrialist Elijah McCallister, Roam once boasted a thriving silk industry.

As the book opens, McCallister is long dead, the ruins of his once magnificent mansion now home to his great-great-granddaughters, Helen and Rachel. Rachel, 18, is as beautiful, as her sister, Helen, 25, is hideously ugly, and the two have been inseparable since their parents died years ago.

It’s doubtful that they will ever leave Roam, much less lead separate lives. One reason is that Rachel is blind. The other problem is Helen.

In contrast to her angelic sister, Helen is a tough and seasoned purveyor of sin. She not only spent her teenage years secretly seducing every local boy she could drag home, but kept busy on rainy days by terrifying her sister with a series of outrageous lies about her looks, the town and the dangers lurking in the woods and ravine that lies just beyond it.

To top it off, Helen tortures the helpless Rachel with reminders of the sacrifices she has made to stay home and be her caretaker. But when Rachel, determined to prove her independence, ends their bruising codependency by vanishing from Roam, Helen is devastated.

The sisters are products of a grand tradition of dysfunctional relationships. A “Short History of Roam” chronicles their great-great-grandfather’s early years and his relationship with Ming Kai, the Chinese silkworm merchant McCallister kidnapped and smuggled to America to teach him the trade. They form a symbiotic but troubled bond that haunts their descendants: Chinese, mixed-race and white alike.

Some of these descendants — Digby Chan, a diminutive bartender; Jonas, a car repairman; and Smith, a Paul Bunyan-like lumberjack — live in Roam and pitch in to help Helen recover her sister — and her soul. Others inhabit a bleak faraway Valley, the place Ming Kai discovered when he, his family and his followers left Roam in hope of finding a better world.

Hovering throughout the town — and frequenting Digby’s tavern — are the ghosts of the town’s once-glorious past, who number so many that their “spirits could no longer be contained in the darkness and, like deer had spilled over into parts of the town reserved for the living.” Wallace, a master of the tragicomic, has said that laughter and tears come from the same neighborhood.

The pervading mood of “The Kings and Queens of Roam” is melancholy and the hope of a bright future is always envisioned as taking place elsewhere. But even its dismal scenes are darkly funny and wildly inventive.

At the heart of this fractured fairy tale is the power of story to alter fate and its moral repercussions: “In a moment, everything can change,” Digby tells Helen. ” ‘One life is this far away’ — he held a thumb and index finger a hair’s width apart — ‘this far away from another one, a different one, a new one.’ ” There’s a wealth of enchantment here — curses, an evil sister, a miraculous spring, teetotaling ghosts, and, most importantly, the transformative magic of loss.

With enough forgiveness, love and maybe even a little vision, these kings and queens of thwarted dreams may finally get their happily ever after.