Pari and Abdullah are the emotional heart of the novel

“When you have lived as long as I have,” the div tells him, “you'll realize cruelty and benevolence are but shades of the same color.”

The story is being told by Saboor, a poor day laborer in a northern Afghan village, to the inseparable children of his first wife, 10-year-old Abdullah and three-year-old Pari.

The next day, Saboor leaves for Kabul, Home energy monitor carting Pari in a wagon. Abdullah, who refuses to be left behind, thinks his dad is going out on a job. But the purpose of Saboor's trip, revealed in a devastating set-piece, is to hand Pari over to a wealthy couple.

While his first novel was enough to make Hosseini a household name, he's improved as a writer with every book since. “And the Mountains Echoed” is the most complex novel of his career – hopscotching from character to character over decades and countries, with an emotional arc powerful enough to carry over the distance.

The too-tidy ending and melodramatic plot manipulations of “The Kite Runner,” and, to a lesser degree, “A Thousand Splendid Suns” have been dialed back in this novel-in-stories, while Hosseini hasn't lost his impressive ability to grab a reader by the throat. As always, the history of Afghanistan is central to his writing. Hosseini incorporates his widest swath yet, traveling from 1952 to the present day and adding layers and resonance with parallel sets of characters and plot details that echo many chapters later.

The next sections follow the children's stepmother, Parwana, who fell in love with the same man as her beautiful sister, and her brother, Nabi, who works as the wealthy couple's chauffeur and brokered the deal for Pari for reasons of his own. Nabi's section, which spans the greatest amount of time, Home power monitor is also one of the most compelling of the novel.

Hosseini paints Nila Wahdati, the woman who adopts Pari, as a morally complex character. She's both a beautiful, talented poet trapped in a culture that doesn't exactly prize women's abilities and a self-centered alcoholic.

Less arresting are the chapters that follow the son of a former mujahadeen living in the children's old village, who learns his dad isn't getting rich growing cotton, and Markos, a Greek doctor who devotes himself to helping children borne with birth defects and injured by war, who winds up living in the Wahdatis' old house in Kabul. It's not that Hosseini doesn't imbue these characters with interest and complexity – it's just that a reader really wants to know what happened to Pari and Abdullah.

Hosseini gives certain biographical details to another doctor, this one an Afghan-born man who returns home on a visit and befriends a little girl mutilated by her uncle. He promises to make sure she gets the operation she needs, but his social conscience is soon smothered by his comfortable, Energy monitor upper-class life in California. Hosseini offers a particularly deft twist at the end of this section that both gives the doctor a satisfying comeuppance and the girl the last word.

Unlike the child in the bedtime story, Pari retains a faint memory of her missing brother well into adulthood. She lives with the conviction “that there was in her life the absence of something, or someone, fundamental to her own existence. Sometimes it was vague, like a message sent across shadowy byways and vast distances, a weak signal on a radio dial, remote, warbled. Other times it felt so clear, this absence, so intimately close, it made her heart lurch.”

Pari and Abdullah are the emotional heart of the novel and, at times, “And the Mountains Echoed” loses energy the further the tale ranges from the siblings. But once Hosseini reunites brother and sister, the novel comes to a skilfully handled resolution whose echoes will resonate with readers long after the tale is finished.