From his first wife, Katherine of Aragon, to his sixth and final spouse, Catherine Parr, the Tudor monarch Henry VIII married for love as well as for politics, but his most potent and enduring union was with another man. In "Wolf Hall" and "Bring Up the Bodies," both winners of the Booker Prize, Hilary Mantel charted the rise of Thomas Cromwell — lowborn son of a blacksmith, sometime mercenary and protégé of the illustrious Cardinal Wolsey — to the king's adviser and alter ego.

Her new book, "The Mirror and the Light," brings home Mantel's trilogy to the place where she began: Cromwell calculating the odds against him as enemies plot in the shadows. It's a stunning capstone to an epic that's both engrossing history and an unsurpassed literary achievement.

The novel unfolds over the last four years of Cromwell's life, opening in the aftermath of Anne Boleyn's execution as he pursues power for power's sake. He's wildly successful: beheading nobles, burning monks at the stake, liquidating abbeys, racking up title after title while enriching his household. (Among the book's many pleasures are the ways Mantel evokes her protagonist's shifts in persona, from trusted minister to cruel inquisitor to gentle mentor, brilliantly capturing the teasing bonhomie of young men at work and play.)

Cromwell's wounded inner child spurs him on as he seeks to loosen England from the iron grips of pope and aristocracy, a transformation not without peril: "These broils begin the same, and from age to age they end the same. The gentry pardoned, and the poor dangling from trees."

He's locked and loaded on a quest for payback, an Elizabethan revenge drama unspooling while Elizabeth is still a toddler in her father's court.

"The Mirror and the Light" is long and lacks the galvanizing presence of Boleyn, whose arc drove the earlier novels. (Henry's third and fourth queens, Jane Seymour and Anne of Cleves, are realized here, but they're no match for Boleyn's Lady Macbeth antics.)

"The Mirror and the Light" by Hilary Mantel

Mantel has far more political ground and plot twists to cover, requiring a reader's patience with the intricacies of backroom deals and the fledgling Reformation. But the narrative never feels like a maze; Mantel's language sings gloriously across the register, from lyric to comic to tragic, her punctuation and use of pronouns as liquid and expressionistic as Monet's brushwork in his late canvases.

And Cromwell? He's haunted by his own mortality, encircled by grim reapers of his imagination. Mantel weaves into her tapestry cemeteries and executions and gravediggers; in one scene the minister oversees the exhumation of Thomas Becket, clasping the martyr's skull, an echo of Hamlet and Yorick.

Her prose blends Renaissance idioms and contemporary slang — "suck on that, Mendoza" — underscoring her melding of the past with our present. Mantel recognizes the birth of the modern in her striver from Putney: "Somewhere — or Nowhere, perhaps — there is a society ruled by philosophers. They have clean hands and pure hearts. But even in the metropolis of light there are middens and manure-heaps, swarming with flies. Even in the republic of virtue you need a man who will shovel up the [manure], and somewhere it is written that Cromwell is his name."

"The Mirror and the Light" is a diadem of riches, binding together the complex pieces of Cromwell's character while leading inexorably toward the scaffold. With the trilogy now complete, Mantel cements her position as one of our greatest literary stylists and innovators.

Hamilton Cain is the author of "This Boy's Faith: Notes From a Southern Baptist Upbringing" and a member of the National Book Critics Circle. He lives in Brooklyn.

The Mirror and the Light

By: Hilary Mantel.

Publisher: Henry Holt, 784 pages, $30.