Behind the Beautiful Forevers, By Katherine Boo. Portobello, £14.99

Katherine Boo's debut about the vertiginousness of existence in a "Mumbai slum" is the antidote to mainstream books and films on the subject from the English-speaking world. It's framed by her noting the lack of "deeply reported" non-fiction about India. Her method, developed "within poor communities in the US", is to invest time and attention in the complex interiors of "small" people.

Boo spent years returning to Annawadi, a community of 3000 people in 335 wonky huts beside a sewage lake near the newly-privatised international airport. Founded by Tamils and home to three dozen Muslim families, this rat-infested "sumpy plug of slum" is supervised by Mumbai's Hitler-loving Hindu nationalists.

The book begins with startlingly acute portraits of Abdul, Asha, Sunil and Manju, each of whom obtains the strange indelibility of fictive characters. Next, Boo activates Annawadi's abysmal dramas and the churning corruptions of its hinterland, before following arterial links through Mumbai into the body of India. It all forms tightly around Abdul, a bread-winning boy blamed for the self-immolation of a one-legged neighbour, and his family's violent, absurd and tragic encounter with Indian "justice".

India flatters itself that it's too mystifying a social entity for foreigners to understand, but Boo spikes that myth with compelling force. This is a finely hewn, gently humoured and tough-minded work of lasting import. It memorialises a place where people survive on sewer-grass and feet bloom with fungi in the rains.

Above all, Boo is convincing. I recognise many details from my own engagements with parts of this extraordinary subcontinent.

Behind the Beautiful Forevers converts everyday extremities and human idiosyncrasy into pared-back prose of great charm. The result combines ethical clarity and writerly exactitude to stimulate outrage and unsettling pleasure.

Guy Mannes-Abbott's new book, 'In Ramallah, Running', is published by Black Dog