I spot it first and in three steps I have it in my hand. I stand and hold it up as if in a victory salute, before I drop it to the floor and smash it with my foot. I hear Aoife giggle and I feel pride in making her happy. It emboldens me.

‘Mary,’ Joanne repeats. ‘Can we wait until Gerry is here?’

‘No.’ My voice sounds distant and unlike my own, but I cling to the words as if to a lifeboat in a raging sea.

Joanne speaks again and I know she’s trying to buy herself some time. I’m not stupid.

‘Gerry says you saved me. Is that right?’

Clever, pulling on my heartstrings. I stay silent. Sirens are in the distance; she hears them too: her look is hope, mine panic.

‘Get her – now,’ Aoife hisses, and as Joanne turns to run I’m on her.

‘Get her out and in the car,’ Aoife says as I wrestle Joanne to the floor. Her breathing is hard because my knee is against her neck, but all I can think about is doing what Aoife wants. Paying her back for what I did.

I pin Joanne’s arms behind her.

‘Come on,’ Aoife says, opening the door, ‘get her to the car.’

I comply, dragging Joanne towards the entrance, acutely aware of the sirens getting closer.

Once outside I open the boot and push Joanne inside.

‘Hurry,’ Aoife calls.

The sirens are so loud now they almost drown out Joanne’s shouts from the boot. I try my key in the ignition and fail.

‘For Christ’s sake, hurry,’ Aoife says, her voice cross and urgent. I panic, shoving the key in as hard as it will go and turning it. The engine roars into life and I feel triumphant.

‘Now where?’ I ask.

‘The beach,’ she replies.

Fifty-seven

Nell, Paul and the uniform backup had found no evidence of Joanne when they’d arrived at her house. Looking through a window, they’d seen a handbag on the floor, its contents scattered, and requested permission to gain entry. Carla and Bremer were now bent over the radio as it crackled on her desk, both listening for updates on the operation’s attempts to gain access to Joanne’s home address.

‘Entry gained,’ the radio told them.

They’d broken down the door, but Carla knew that was when the danger began. The first potential flashpoints were the front room and downstairs toilet.

‘Downstairs empty and secured.’

Carla bowed her head in relief. She’d never managed to move from paper analyst to real-life operations, the fear her analysis might result in an officer’s death being too much to bear. But hearing that the downstairs was empty came with feelings of relief and frustration, because that meant the upstairs had to be searched – a far more precarious scenario – as well as the possibility that Mary had managed to evade them.