Khaled Hosseini’s book about the hopes and miseries of half a century of Afghan history, as evoked by the relationship between two pre-teen boys, has been considerably – and justly – acclaimed; first turned into a film, and now into a play, each version serving to reveal far more than a country riven – by post-Colonialism, Communism, tribal and religious hatred – for here we have s a cross-section of human life, of guilt and arrogance and postures; a mythic tale, much like the story of Sohrab and Rustum (or Shahnameh), medieval Persia’s national epic, in which a battle-hardened father unwittingly slays his son.

Father-son antagonism, differing layers of male pride, and the puzzling rituals of male adolescence, are all at the story’s heart. Resentments, betrayal, the urge to atone: these are issues Giles Croft’s production, fired by Matthew Spangler’s shrewd adaptation, bring to the fore.

Croft’s is a very good production indeed: economical, exquisitely cast beautifully paced, and scrupulously loyal to the original novel. The emotions, often buried and awaiting articulation by the elder boy, Ben Turner’s eager-eyed Amir, simmer like hidden volcanoes. It is a production where, much like an iceberg, four-fifths of the raw human anguish is buried beneath the surface.

But we see a lot. There’s the healing wisdom of Nicholas Khan as the family friend, Rahim Khan, who reconciles the adult Amir with his blighted teenage past, his lost nephew, and the brother he never knew (the Persian epic again). And the increasingly arthritic, cheerfully shark-toothed, self-made paterfamilias (‘Baba-Emilio Doorgasingh), whose every appearance (even when humiliated in Jimmy Carter’s America: ‘I do six days a week, 12 hour shifts as the gasoline station’) brings conflict and insight in equal measure.

Or Antony Bunsee, poker-faced and erect as a Hazara-despising Pashtun top brass (General Taheri), pride in social caste etched plain on his military features.

Before the boys, with their romping prepubescent innocence, come the roughs: a bullying trio who give vent to their cowardice victimising the younger pair, Amir and Hassan. Leader Assef (beautifully concocted by Nicholas Karimi, an incipient Tybalt, who evolves into an oversexed Taleban monster), practises his streetwise dictatorial skills by raping Hassan.

You don’t quite see it, but you half-glimpse it, feel it, and it echoes throughout the play. Afghanistan, like warlord Africa, offers a playground to rapists, a place where seed flows amid the blood. Yet even this too, though it mirrors horrific reality, is a metaphor: Karimi’s priapic assault exemplifies the sterility of Communist, Taliban, Northern Alliance, even Karzai’s Afghanistan.

Hanif Khan, on tabla, provides atmospheric onstage music. His material seems mixed, but there was no doubting his rhythmic sense, presence and noble, relaxed execution. More central are William Simpson’s stunning back-projection effects; none more so than a pair of kite-like drawn curtains that changed kaleidoscopically with each unveiling. A palisade metamorphoses into Golden Gates and skyscrapers; such beautiful lepidopteran economy saying more than a hundred set changes.

But it is the two central characters, and above all Ben Turner’s Amir, who make this production so moving. Here is a boy aghast with wonder (two kite-flying sequences, the last breathing life into the retrieved mute son Sohrab, were electrifying), whose adolescence is sullied by appalling, part-unwarranted, guilt. Despite some wobbly accent work, his Turner holds us in edge-of-seat fascination for two and a half hours. Thanks to his passionate honesty, Spangler’s scenes seem to fly by.

Farshid Rokey, as the disconcertingly unjudgmental Hassan, who conceals his rape to protect the friend he knows witnessed it without intervening, is all slouched shoulders, furrowed concentration, desperate side-glances, and almost shamanistic silences; and then as Hassan’s long-lost son – this is one of those plays that explains reincarnation right before your eyes – his is, with David Ahmad’s orphanage head, the performance of the evening. But this is a play with duende in droves. Praise to Croft for peeling back the layers.