Desperate for fresh air, as soon as DC Roberts leaves, Sienna is in her car, heading towards the North Circular towards Hanger Lane. The traffic is almost at a standstill, but she doesn’t care. It’s better than facing her empty house.

She has no idea that, at this moment, Abby is knocking on her door.

It’s long after lunchtime when she arrives back home, and she stays in her car, still with her seat belt on, dreading stepping inside to be confronted with the helplessness and loneliness that waits for her. One thing is clear – inaction will floor her; she has to keep moving.

She reaches for her phone and texts Abby.

I’ve just spoken to the police. Are you ready to tell me the truth?

Although she’s certain Abby won’t reply, part of her hopes she might agree to meet, that they will discuss everything, and by the end of the day she might be closer to knowing where Greg is.

A reply comes within minutes.

Sienna, I really don’t know what you’re talking about. Please let me help you, or get it from someone else if you prefer, but don’t do this to yourself.

And that’s when she explodes, her scream filling the car.

Sienna’s mobile rings in the late afternoon, and she rushes to answer it without checking who’s calling. In the first silent millisecond she can almost hear Greg’s voice greeting her, telling her that he is sorry, begging her forgiveness.

‘Sienna? Hi, it’s Holly. How are you doing?’

She snaps alert. A friendly voice at least. ‘I’m… okay.’

‘It’s okay not to be,’ Holly replies. ‘I’d be in pieces if it were my partner who was missing. Look, I know I stopped loving Greg a long time ago, but he’s Jackson’s father, so I do care what happens to him.’

Her voice is different over the phone, deep and soothing. Had she sounded that way when Sienna turned up at her office? It’s hard to recall. ‘Thanks, Holly.’ She’s unable to fully express how much this woman’s words mean to her.

‘Anyway, I wanted to let you know that I’ve told Jackson.’ She lowers her voice. ‘As you’d expect, he’s not taken it well at all. He burst into tears and has barely said a word since. I knew this would be hard on him, so I tried to tell him his dad was just taking a break by himself, but Jackson can’t be fooled. He knew immediately that something was wrong. He said Greg would never leave without telling him.’

Holly’s words penetrate through her. This is true, so why hasn’t it occurred to her before? No matter what, Greg would never leave Jackson.

‘I’m so sorry he has to go through all this,’ Sienna says.