A Quiet Adjustment, By Benjamin Markovits

In the prologue to his previous novel, Imposture, Benjamin Markovits describes a teacher who "spoke Romantic like a mother tongue". The prologue proved to be a postmodern framing device for a novel about Byron, from the point of view of John Polidori, Byron's physician. The fluent Romantic speaker is, of course, Markovits; and in this second novel of a planned trilogy about Byron, he returns to what's beginning to seem like his native tongue.

A Quiet Adjustment continues Markovits's fictional portrayal of England's most notorious poet through the prism of three people close to him. (We don't yet know the third, but Byron's sister, Augusta Leigh, must surely be a prime candidate.) Here the focus is on his wife, Lady Annabella Milbanke, who prefers reading to embroidery but fills her days with gossip, parties and dances. At an "after breakfast waltzing party" at the home of Lady Caroline Lamb – rumoured to be Byron's lover – Annabella glimpses the famous poet. At a lecture a week later, she sees him again. Asked by her mother what she learnt, she is tempted to answer "the shape of Lord Byron's head".

She is, of course, sunk. In time-honoured fashion, she rejects the proposal from the sensible but pompous suitor and instead nurses her obsession for the man who tells her that "the great object of life is sensation". "He is not," she asserts in response to a warning from a friend, "a dangerous person to me". The proposal comes and, after an initial rejection, is repeated. They are married on a cold, winter's day. "You cannot love me as I am," he tells her on the first day of their honeymoon, against a background of pathetically fallacious snow. "'That," she replies, "is what I have vowed to do".

A Quiet Adjustment is, essentially, a chilling portrait of an abusive relationship, which begins with glimpses of the poet's casual cruelty to his wife, continues with cameos of his calculated brutality and builds up into a picture of what used to be called a psychopath – and has always been called a monster. The question, as always, is why any woman would continue to subject herself to this kind of torture. The answer that Markovits supplies – a complex mix of lust, self-delusion, arrogance and that familiar, fatal addiction to charisma – is brilliantly, and convincingly, done.

It's complicated by Annabella's relationship with Byron's sister, Augusta, who is also, she learns, his lover. Yearning for a close woman friend, Annabella loves Augusta, envies her and tries both to protect and to hurt her. The normal human mix, in fact – the mix that Markovits handles, as always, with ease and panache. With epigrammatic brevity appropriate to his adopted Regency tongue, he offers insights of such startling acuity that they sometimes make you gasp.

This is prose of extraordinary richness and subtlety, rich in nuance and irony. Avoiding the pitfalls of pastiche, it aims to offer a flavour of the period and its rhythms. Very occasionally, the sensibility seems a little too contemporary. Occasionally, too, Markovits's use of the tropes of the Gothic novel – Scott's "open, manly countenance", "rueful" smiles – sail a little too close to cliché. His habit of enclosing reported speech in quotation marks is both confusing and irritating.

A Quiet Adjustment has a slower start than his previous novels. It is, however, a hypnotic, impeccably researched, and dazzling glimpse into a psyche which has fascinated the world for nearly 200 years – and will no doubt continue to do so.

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