In the Kolkata of Megha Majumdar’s gripping second novel, set over seven days in an unspecified ‘ruined year’, restaurants deliver meals to the rich under cover of darkness. Others in the pestilent, depleted city do what they must to feed their loved ones – storming ration shops, looting the pantries of the well-to-do, even battering old women for a fistful of green beans.

A Guardian and a Thief follows Majumdar’s virtuosic debut, the political fiction A Burning. It opens a week before the flight that is meant to take a woman, known only as Ma (Bengali for ‘Mother’), along with her young daughter and widower father, from Kolkata to Michigan, where Ma’s husband, a research scientist, awaits them. In the meantime, the child needs to eat. Hence the cache of eggs, ‘speckled gray like the moon’, cashews, milk powder and dried fruit – filched from the climate-refugee shelter Ma has been managing – hidden in ‘the dark fist’ of her family’s house. Until Ma lands a job in America, she plans to supplement her husband’s wages with bank notes pocketed from the same source – this in spite of the couple’s middle-class savings.

On the second day, Boomba, a wrecker with a touch of the picaresque, breaks into ‘manager madam’s’ house, plunders the food supply and makes off with Ma’s purse, which contains the passports. When he finds that the strange booklets have no practical use, he tosses them to the edge of a rubbish heap. He’s after food, money and a place to settle his family, one that ‘allowed neither mosquito nor rainwater nor robber to assault them’.

Blackmail and a missing child are just two links in a chain that holds the antagonists together with terrible, classical force. If an ecological crisis exposes the savage underbelly of selfless familial love, this compressed novel suggests, then its licensed brutalities are engendered by the failures of the polity and its structures.

Occasionally the author interrupts the narrative with omniscient commentary that thinks for the reader and states the obvious (‘No, Boomba was no monster. All Boomba was was a man whose moral compass pointed to the north of his own family’). Still, A Guardian and a Thief is an impressive novel. Pages suffused with ambient menace also accommodate tenderness – for evanescent sights, such as that of an orange ‘with a small leaf on the stem like a flag of discovery planted upon a planet’s pole’.