I packed up our overnight bag and took Freddie to Hyde Park whilst Jen took the girls shopping for clothes. I pushed him on the swings and held him tight on the see-saw to stop him bouncing off through the air, whilst he giggled raucously, and all the time my mind rattled back to Lord Higham. Why this vendetta now? Where did this all link up? I had done nothing to hurt Dalziel; I’d loved him very much, adored him even. So why did I feel now like I was being held accountable for the past?

Something had happened somewhere, and I was missing the obvious clue. I needed to speak to James again, but there was no chance of that for at least a week.

‘Which superhero do you want to be, Mummy?’ Freddie said as I lifted him to ring Jen’s doorbell.

‘Batman?’

‘No. I’m Batman.’ He considered me kindly for a second. ‘You can be Under-woman if you like.’

‘Under-woman? OK.’ I kissed him and plopped him down on the pavement again.

‘She wears big pants actually. And a cake.’

‘Big pants and cake?’ He meant cape. ‘My type of lady.’

A man suddenly stood behind us, too close. ‘Mrs Miller?’

My scalp prickling, I glanced round, clutching Fred’s hand tighter.

‘Would you accompany me please, Mrs Miller.’ It didn’t sound like a question. Quickly I pushed Fred between me and the front door.

‘Sorry – who—’

‘Lord Higham would very much like to see you.’ He was politely unsmiling. ‘Now.’

‘Now?’

‘It’s important.’

‘I’m sure it is, but as you can see,’ I picked my protesting son up again, ‘I’m busy right now.’

Jen opened the door, Effie in her wake.

‘I’m sure your friend can help out,’ the man said. He had a very faint accent and greasy pock-marked skin. ‘Can’t you, madam?’

Jen’s eyes flicked anxiously between us. I hesitated, rapidly weighing up my options. Then I pressed Freddie into Jen’s arms, kissed Effie’s head and turned away. A black limo purred at the kerb, the windows darkened.

‘I’m really sorry, Jen. I’ll explain later.’

‘Are you sure this is wise?’ She looked worried. ‘Where are you going?’

‘Take down the number-plate,’ I muttered into her ear, ‘and if I’m not back by six, call the police.’

I followed the man to the car. ‘See you for pizza in a minute, kids,’ I called, waving cheerfully. ‘Do what Auntie Jen tells you, OK? And no fighting.’

The man didn’t quite push me in, but his hand was merciless, and when he slid into the front, he locked every door.

In an alleyway somewhere between the Houses of Parliament and Victoria Station, I was led past great stinking bins through a cramped and sweaty kitchen into a tiny dark restaurant.