I shrugged. ‘What do I know?’ I said. I was thinking of making it my family motto.

‘Maybe we should ask her,’ said Kumar.

‘And destroy the mystique?’ I said.

Kumar wanted to know how magic worked but I told him that I was supposed to keep it secret. ‘I’m already in a ton of shit for opening my mouth,’ I said.

Despite that, he asked whether it was element based – fire, water, air and earth. I said I didn’t think so.

‘So no Earthbenders kicking rocks around,’ he said.

‘Nope,’ I said. ‘Or Airbenders, or Waterbenders or He-Man or Captain Planet.’ Or any other character from a kid’s cartoons. ‘At least I hope not. What kind of stuff do you get down in the tunnels?’

‘Lots of ghost reports,’ said Kumar and started digging through the catering boxes. ‘Not as many as we get from overground tracks.’

I thought of Abigail’s deceased tagger.

‘Anything else like the guy with the machine gun?’ I asked.

‘There are always rumours that there’s people living in the Underground,’ he said.

‘Think it’s likely?’ I asked.

Kumar gave a happy grunt and emerged from the box with a multipack of cheese and onion crisps.

‘I wouldn’t have said so,’ he said. ‘The sewers are toxic, it’s not just the risk of infection or disease—’

‘Or drowning,’ I said.

‘Or drowning,’ said Kumar. ‘You get gas build-ups, methane mostly but other stuff as well. Not very conducive to human habitation.’

I thought of the big eyes set in a pale face. Too pale perhaps?

‘What if he wasn’t entirely human?’ I said.

Kumar gave me a disgusted look. ‘I thought I was used to investigating weird shit,’ he said. ‘I really had no idea, did I?’

‘No idea about what?’ asked Reynolds from the doorway. ‘Shower’s all yours by the way.’

We showered and then stripped, which is how you do it when you’re covered in sewage. I had a row of spectacular bruises across my chest that I knew were going to come up good and purple in the next twenty-four hours. Kumar showed me how to wring out coveralls and then we put all our, still damp, kit back on – including the Metvest. Especially the Metvest.

Me and Kumar agreed that I’d talk to the sisters while he checked in with his boss, my boss, my other boss, Seawoll, and, finally, Lesley. This is why nobody likes joint operations.