As engrossing as any thriller, Anosh Irani’s fourth novel offers readers so much more. An aggregate of storytelling accomplishments, The Parcel captivates with its vividly rendered characters and commands the reader’s attention by way of unnerving – and at times profoundly disturbing – portraiture of an abject group at the bottom of an already denigrated community at the heart of India’s booming financial hub, Mumbai, itself an impossibly complex and rapidly changing metropolis of some 12 million souls.

Rather than opting for a roving or panoramic approach (India’s wealthiest city covers more than 600 square kilometres) Irani restricts his focus to Kamathipura, a destitute, violent, and thriving (though also scandalous and taboo) district composed of 14 teeming lanes that house an economy based on crushing, slavery-like sex work.

Irani leads readers on a memorable walking tour though what is likely alien territory for them, but his primary focus is one resident of a specialized brothel. At 40 years of age, Madhu is no longer a prostitute. A street beggar and frequent right hand for her elderly boss, she regards herself as detritus – “already dead,” or “a mere lemon peel lying on the road.” Before retiring at 35, she had plied her trade for decades in what she calls the “garden of rejects.”

Born with male genitalia, but virtually disowned by her parents, who regarded an effeminate boy as an affront and shame to the family, Madhu left home and was taken in by a powerful woman – a gurumai – who became an ambivalent maternal figure as well as an employer and master. Following the ritual castration of Madhu at 12, and without anesthetic, the gurumai’s ward began working to pay off an accrued debt.

As a hijra (the word’s roots are twofold: from the Persian for “effeminate, impotent, or hermaphrodite” and Urdu for “migration”), Madhu endures a staggering array of abuses but, for a time, flourishes as a brothel headliner whose “arsehole,” she recalls, “was a cash crop.”

As conveyed by Irani, sheer outrageousness and deeply earthy humour are among the sex-trade worker’s raucous strategies for survival. The routine inclusion of vulgar humour’s feral bite gives Madhu and her sisters a humanity that is missing from the city’s supposedly upstanding citizens, who spit on the members of the underclass and wish them dead.

Near the novel’s start, Madhu is assigned a task for which she gains local renown: she must prepare a “parcel” for opening. The parcel in question is a preteen Nepalese girl who has been sold to the brothel; in a short while she will meet her first client, who has paid a bounty for her virginity. Madhu’s job is to ready the girl, Kinjal – who is locked in a cage in a darkened room – for the new realities she will need to survive.

Madhu’s techniques involve trickery, psychological torment, and opium pills. She believes that her approach teaches a girl she is worthless and cannot escape her fate: coming to understand this, Madhu believes, is better than clinging to false hope. It also lessens the likelihood of rebellion or suicide. Madhu has learned from the techniques of others: “The pimps prepared the parcels for whoredom by plundering them beyond belief, turning them into vegetables.”

Irani unflinchingly portrays Kamathipura’s harrowing everyday realities, including – but not limited to – rapes, beatings, degradation, derision, suicide, AIDS, TB, and opiate addiction. He also depicts the district’s complicated social organization, beliefs, rituals, and friendships.

The various episodes in the novel are deeply affecting, giving the reader ample reason to agonize over the fact that such a place exists at all, and that its hourly miseries are an ordinary aspect of people’s lives. Irani’s compassion for these discarded souls, and the assertion of their essential dignity, renders them simultaneously touching and distressing.

In part, The Parcel hinges on the question of how Madhu – herself raging and despondent, but with a constitutionally caring aspect – will act as the day of the parcel’s “opening” draws nearer. As the novel unfolds, Irani weaves in fascinating plot strands about changes to the brothel’s organization, Kamathipura’s status within the larger metropolis, and Madhu’s recollections of her family and experience following her departure from her unwelcoming home. All of these elements play important roles in Madhu’s gradually altered outlook and decisions.

“Born and bred to mortify,” Madhu is a breathtaking figure, admirable despite that fact that the “very things that made one human – love, hope, health – had been ripped from her calmly and precisely, the way a syringe extracted blood.” Bitter, despairing, self-hating, resentful, and cynical, Madhu is also filled with tremendous longing and dreams for a life she’s quite certain will never manifest. She’s a marvellously nuanced character and a signal achievement for her creator. In Irani’s vision, Madhu and her community become a fierce indictment of the hypocrisy and indifference of civilizations content to turn a blind eye on human suffering and indignity, rather than pondering some brutal truths.