A light brown haze slowly but surely envelopes the stage as the audience fills into Olivier Theatre at the National Theatre in London. It is one of the first defining visual moments of director Rufus Norris's stage incarnation of Katherine Boo’s non-fiction book Behind the Beautiful Forevers – transporting the audience into the concrete-dust infused reality of a rapidly expanding megacity. On display are the sights of Annawadi, the Mumbai slum that was brought to the world's attention in 2012 by Boo’s stunning book, which contrasted the city's poverty with its growing economic prowess.

The rise of the 21st-century globalising city, the world-wide recession and the economic ambitions of upper-class India jostle for a central role in the narrative with the stories of Abdul, a garbage recycler; Asha, a rare female slumlord; Zehrunisa, Abdul's foul-mouthed but proud mother; Fatima, the one-leg laughing stock of the slum; Manju, Annawadi's soon-to-be-first-female college graduate; and finally, Annawadi itself, as a stage, a spectacle and a voyeur’s delight.

Boo's book presents a strong image of this location: a swirl of construction debris, a sewage lake, miserable shanties, colourful characters, airplanes roaring overhead, blinding glass buildings, aluminum fences, garbage and some more garbage. The National Theatre's renowned technical expertise brings Annawadi to life with all its drama of showering plastics, shadow-play airplane visuals and set changes involving its revolving stage. For all  practical purposes, this is what a slum looks and feels like.

The Slumdog Millionaire trap

But in this adaptation of Boo's book by playwright David Hare, the spectacle takes precedence over the narrative, falling into the Slumdog Millionaire abyss of recreating slums but disconnecting them from the lived experience of people who are different from us.

The play flails, for instance, when many of the British-Asian actors in the cast attempt to portray the residents of Annawadi in a hybrid Bambaiya-infused, almost unnatural English. For someone from Mumbai, the effort seems forced. It’s jarring, because the book made these language barriers seem irrelevant. Hare's script tries to faithfully recreate some of its nuances in the raw recreations of the fights between Fatima and Zehrunsia. But many of these attempts are thwarted by the casting:  British actor Chook Sibtain playing a Maharashtrian sub-inspector with his clear London-accent; the relatively clean-looking Hiran Abeysekera as a stunted 11-year-old Sunil, a choice made even more strange by the appearance of a six-pack when he does headstands; Shane Zaza as the inward-looking, shrunken Abdul repeatedly trying and yet falling just short in his attempt to bring Abdul to life.

But then again, some other actors shine, both those with major parts and others in smaller roles. Meera Syal captivates as Zehrunisa, Stephanie Street sparkles as Asha, Anjana Vasan’s Manju, who tries hard to grasp Virginia Woolf’s Mrs Dalloway, forms the delicate idealistic bridge between the educated rich and the poor, while Thusitha Jayasundera’s Fatima is effervescent and all-consuming, appearing both hard-edged and empathetic. Muzz Khan as the havaldar is perfectly caricatured in his comic cluelessness, while Mariam Haque as the female havaldar is a waif-like power-wielder. Nathalie Armin as the power-broker Poornima Paikrao drives her knife down our throats.

Could the grand spectacle of contrasts have been accomplished without projecting this multi-dimensional mass of poor folk against the cardboard cut-out of the “first class people”, as Asha puts it? Can the lived experience of a Mumbai slum be recreated for an audience that can only visualise rather than experience it?  Designer Katrina Lindsay draws from strong reference points in the book and existing ideas of Mumbai slum glam. Scene changes are punctuated by jarring Bollywood numbers, the auto-rickshaw and the tempo make guest appearances, while police stations, government hospitals and court houses have also been recreated.

As a work emerging from the verbatim/documentary theatre tradition, and the fact that it draws from Boo's deeply immersive reportage, this fast-paced adaptation is faithful in its promise to bring to the stage the actual words of real people.  In the end, however, it might leave some cold. You empathise with the characters, but don’t feel close to them. Lessons are learnt, slum life surveyed and enlightenment perhaps dawns on those for whom this gritty world is new. But for an audience unfamiliar with the context of slum life, watching it on stage is at best an arms-length experience.