The immortal figures of Anne Rice’s Vampire Chronicles are starting to show their age in “Prince Lestat and the Realms of Atlantis,” the 14th book in a series that began 40 years ago with “Interview with the Vampire.” The new novel’s title hints at the problem that besets the prolific Rice in her most recent foray into the supernatural: Having populated her literary worlds with vampires, werewolves, witches, demons, ghosts, angels and the Holy Family, what’s left? Some might have suggested zombies, but shambling corpses would presumably present too many wardrobe challenges. The expensively attired characters in this book and its predecessors wear enough fine cashmere, silk and kid gloves to furnish their own undead Barney’s boutique.

So, this time out the vampires confront entities not of this earth, although the newcomers’ provenance isn’t immediately apparent. Neither is the plot — it takes about 70 pages for the story to gain momentum. As with the previous volume, “Prince Lestat,” there’s a huge amount of too complicated, not-very-interesting backstory to wade through. (For those uninitiated into the Blood, Rice provides a glossary and two appendixes.)

[Lestat returns: In her new novel, Anne Rice revives a much-loved vampire]

In a nutshell: Not all vampires get along, and most have divided into two camps. Prince Lestat is the good guy. Rhoshamandes is his foil. Lestat is host to a disembodied spirit, Amel, who may or may not be a good guy or its ectoplasmic equivalent. Roland, a friend of Rhoshamandes, has imprisoned a young man named Derek in a dungeon beneath his Budapest manse. We know Roland is a bad guy because he is introduced as “the evil master of the house and its prison dungeons.” Even more ominous, his name doesn’t appear in Appendix 1.

Derek looks human, but he’s not. For 10 years, Roland has kept him as a sort of All You Can Drink buffet. As he tells Rhoshamandes, “You can’t kill him . . . no matter how much you drink. Drink as much as you like, I mean this, as much as you ever drank from any victim. You’ll never feel the death pass into you because he won’t die. He will lie still, without a pulse, without a breath. But then the blood will begin to regenerate and, within an hour or two, he’ll be as he is now. Healthy, whole.”

Derek is a fascinating creation — seemingly immortal, sensitive, prone to frightening flashbacks in which he witnesses the destruction of a city, Atalantaya, that for readers may evoke the fall of the twin towers. He also retains memories of several sibling companions. Over the ensuing chapters, we meet Garekyn and Kapetria, who works for a major pharmaceutical company headed by (need you ask?) a vampire. Like Derek, Garekyn and Kapetria pass as human and have the same recurring vision of the fall of Atalantaya.

Author Anne Rice (Michael Lionstar)

The chapters detailing how these immortals reunite with each other and eventually engage with Lestat and his cohort are the best part of Rice’s novel. Where did they come from? Why are they here? And what is their relationship to the spirit Amel, whose role in the history of both vampires and the lost city of Atalantaya may link not just these deathless beings, but all of humankind as well?

“Prince Lestat and the Realms of Atlantis” falters when it veers from supernatural into science fiction. Rice’s familiarity with that genre seems to stem from retro sci-fi movies and TV rather than science-fiction literature, and the story that unfolds seems ready-made for “Mystery Science Theater 3000.” The glittering, domed city of Atalantaya resembles nothing so much as an upscale shopping mall — solar-powered, with computers and a fiber-optic network, meditation centers and restaurants serving exquisite vegetarian meals, except for the annual Days of Meat, when everyone gorges on beef. There’s also an unfortunate whiff of pulp-era “lost race” tales by writers like H. Rider Haggard and A. Merritt, with a pale-skinned ruler dispensing benign wisdom from above.

Rice’s novel is most affecting when it confronts the issues of mortality, human suffering and religious belief, central concerns throughout her long career. As Kapetria learns more about the role she and her siblings were designed to play in Atalantaya’s destruction, she begins to question everything she had been taught about the city and those who inhabit it, as well as everything she believed about those who raised her. (In this, the book brings to mind Ursula K. Le Guin’s great short story, “ The Ones Who Walk Away from Omelas.” )

Ultimately, “Prince Lestat and the Realms of Atlantis” juggles too many elements: vampires, extraterrestrials, etheric bodies, cellular regeneration, theology, Theosophy, ancient legend and bygone science fiction among them. “It hurts my head to keep talking about cells we can’t see,” Lestat complains near the end of the book. Some readers may agree, and wish for a return to the days when the melancholy adventures of a single immortal denizen of the night were enough to power a novel.

Elizabeth Hand’s most recent novel is “Hard Light.”

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