Her growing confusion creates a surge of frustration through Kat’s limbs, and she suddenly feels the urge to lash out, to find a punchbag and pummel it to death. Just when she was rebuilding her friendship with Beth, starting to make up for the mistakes of her teenage years, someone comes along and threatens to undermine everything she’s achieved. And of course it would be Saskia with her flounce of blonde ponytail and sneering, overconfident expression.

Once the detectives had driven off, Saskia had got her phone out again, tap-tap-tapping on it like the addict she is, before she finally walked inside her own house across the road. The woman is so prolific on social media that she could have been typing anything, but Kat bets she was messaging Beth, telling her about Mark and the detectives knocking at her door, scrabbling for Beth’s gratitude for providing the warning. Kat wonders how Beth will react to the news. Will she be relieved that Mark’s no longer a threat, or horrified about being dragged further into a scandal? Will she race back home to face the detectives or stay away for longer?

This all matters; Kat knows it does. But her mind’s not working properly, and she doesn’t know what to do. She pushes away from the gate and starts walking, onto Brookhill Road and down the hill; she’ll get the bus to Tooting, check on Mark. But she stalls, shakes her head. No, that’s a stupid idea, far too risky. She turns back up the hill. She should go home. Ask Jayden if she can have an hour in his and Will’s garage. Expel some energy, for everyone’s sake. But surely she needs to find out how Mark is? She turns back down the hill, shaking her head and muttering to herself.

‘Are you all right, Kat?’

She looks up. Shit. Saskia is supposed to be in her house; Kat watched her walk inside. Why is she on the street again? ‘Yeah, I’m fine,’ she answers, but her voice warbles. She puts her hand to her throat and tries again. ‘Why are you asking?’ But now she sounds defensive.

‘Okay, sorry.’ Saskia raises her palms. ‘You just look a little upset, I suppose. Are you due at Beth’s? Simon usually runs with Luna on a Saturday morning, so I doubt they’ll need you today. But maybe you got your wires crossed?’

Fear and frustration collide and explode. ‘God, you don’t stop, do you?’

‘Sorry?’

‘Acting like you know everything about Beth’s life. Always digging, digging, digging.’ Kat curls her fingers and scratches at the air, her face pulling into a grimace.

‘Now hang on …’

‘She doesn’t like you, you know.’ The words tumble out. ‘She told me how nosy you are, always wanting to know her business.’ Kat teeters forwards, imagines shoving Saskia in the chest.