In her brilliant new novel, the British writer Tessa Hadley explores her own version of the English country house. Her version is not as grand as Kazuo Ishiguro’s in “Remains of the Day’’ or Ian McEwan’s in “Atonement,’’ but her novel joins those two in using an isolated house as a laboratory in which both past and present act as catalysts to reveal the characters to themselves, to each other, and to Hadley’s deeply fortunate readers.

“The Past’’ has a simple, almost Chekhovian premise: Three sisters, a brother, and their children gather at the family house in Kington, the vicarage where their mother, Jill, grew up, to decide whether they should keep it. Each of the siblings makes a typical entrance. Alice, the middle sister, the would-be actor and poet, arrives in a taxi with Kasim, her ex-boyfriend’s 20-year-old son, whom she has impulsively, and without consulting her sisters, invited. She has forgotten her keys and the two explore the nearby churchyard until Fran, the schoolteacher, arrives with her two young children, the irresistible Ivy and Arthur, and a car full of groceries but no husband; Jeff, a musician, has gigs to play. Meanwhile, Harriet, the oldest sister, who works with asylum seekers, has already arrived and is out walking in the woods, appreciating the birds. Her absent partner, Christopher, remains a shadowy background figure. Lastly, there is Roland, the philosopher brother. He phones when the others are already eating dinner to announce that he, his third wife, Pilar, and his 16-year-old daughter, Molly, will arrive the following day.

More important, however, than the arrival of any single character is the presence of Hadley’s immaculate prose. She is the author of five novels and two collections of short stories and from the opening paragraph we are in the hands of a writer who pays attention to everything: the jostling of the stream at the bottom of the garden, the wings of midges hovering in the warm afternoon air, the self-deprecation of a 46-year-old woman who does not want to appear foolish to a handsome young man. The omniscient point of view is used in many classic novels we cherish but has relatively few contemporary practitioners. Among them Hadley is in the first ranks, and “The Past’’ is a wonderful reminder of the deep pleasures of this technique.

She moves deftly among her characters and, over and over, she writes sentences and phrases that made me gasp. Here is Ivy in bed: “she descended the ceremonial staircase of her sleep, shedding a heavy cloak on the steps behind her.’’ Here is Harriet walking in the woods: “a pigeon broke out from the trees with a wooden clatter of wing beats.’’

But “The Past’’ is not only a novel of sensibility. Hadley has a plot, indeed several plots, and a sense of dark menace lurks beneath the country idyll. I would be doing readers a disservice to reveal too much. Suffice to say that the obvious happens — Molly and Kasim, the only young people in a place with minimal cellphone coverage, become interested in each other — but that interest plays out, with the help of Ivy and Arthur, in unexpected ways. Moreover this is not the only, or even the most passionate, romantic drama erupting in the household. Hadley’s plots unfold in a very natural way. There is nothing forced about how her characters are transported by unfamiliar feelings and find themselves acting in strange ways.

This naturalness is particularly evident in the middle section of the book, which describes the occasion in 1968 when Jill, fleeing her marriage, returns to the vicarage with Harriet, Roland, and baby Alice. (Fran is not yet born.) Jill’s story, another version of the past, is offered without commentary. What a mysterious thing a family is, Hadley seems to be saying. How is it possible that so much of human existence depends on something as irrational, as inexplicable, as random as romantic love?

But Hadley is wonderful at other kinds of love, too. Many of my favorite moments in the novel concern the three sisters. When Fran points out to Alice that Kasim’s presence means she’ll have to sleep with the children, Alice at once offers to do so. “Don’t be silly, Fran said flatly, punishingly. You know that isn’t ever going to happen.’’ The sisters are often impatient with each other, quick to anger at old arguments, but they know each other in deep ways and that knowledge, finally, saves them.

I finished “The Past’’ sadly — why did it have to end? — with a sense that I had understood something profound about both Hadley’s characters, and my own life. Many readers will, I suspect, in the presence of this exhilarating novel feel the same.

By Margot Livesey | globe Correspondent

THE PAST

By Tessa Hadley

Harper, 311 pp., $26.99

Margot Livesey’s new novel, “Mercury,’’ will be published in the fall of 2016. She teaches at the Iowa Writer’s Workshop.