They looked nervous. Some of them wanted to get off, and did so quickly the moment the doors opened, jumping the gap and hurrying quietly away. Those getting on were frowning, glancing behind them, hesitating before boarding.

The buzzer sounded, the voice intoned. The red lights at the rear of the train receded into the black tunnel, grew faint, winked out. The flurry of litter stopped wafting on the track bed, and was still.

Mama took a pair of cotton gloves from the cleaning cart, and a black bag. She passed them to Mary, then helped herself.

‘Aren’t you supposed to be telling me what Mr Nicholls was saying?’

‘Oh, it’s nothing worth wasting your time on, or mine, either. Now you stay out of trouble, girl.’

‘Yes, Mama.’ Mary pulled on her gloves and flexed her fingers, watching the woman dole out supplies and advice to the rest of the shift. Most of them were women, none of them British except Nicholls, and he didn’t really count as part of the team. He didn’t do any of the work, just looked occasionally at his watch when he thought they were behind time and cracked the whip a little harder.

The three little tunnel lights winked from white to red. The rails were no longer live, and it was time to get to work.

She wasn’t the first to lower herself down into the suicide pit, the deep gap between the running rails, but there was plenty of debris for her to pick up. Scraps of paper, sweet wrappers, more copies of the bloody Metro than she could count, buttons, coins domestic and foreign, articles of clothing – the baby socks and shoes she could understand, but the items belonging to adults? Seriously? – empty wallets thrown in by pickpockets, phones dropped by tourists, plastic bags, tin cans, bottles, pairs of glasses, and the thing that had freaked her out at the start but no longer bothered her: hair.

Teased out of passengers’ heads by the whirlwind of passing trains, it formed spidery clumps, not just at the stations, but deep into the tunnels where it had to be picked out from the rocky ballast, by hand, by people like her.

Earrings weren’t uncommon. Mainly paste with plated fittings, but occasionally something of worth turned up. And rings. Mary often wondered about those. Had they been lost from a cold hand, much lamented and impossible to replace. Or had they been torn off in anger and thrown under the train in an evocation of sympathetic magic that would have the ring-giver similarly cast under the wheels of an oncoming train? It wasn’t called a suicide pit because it saved lives; rather, the concrete trough was there because it made it easier to retrieve the broken, scattered bodies afterwards.