Yesterday evening she went to Abby’s house. She’d gone there as a warning, to show Abby that she is prepared to do anything to find Greg. Of course, it would be much simpler if she’d just tell Rob what she knows, but there are several reasons why this isn’t a good idea. If she comes straight out with it then there is every chance Abby will deny it: it will be her word against Sienna’s. She knows enough about Rob’s feelings for Abby to believe he would so easily be blinded to the truth, without something more concrete to convince him of Abby’s guilt.

As well as this, even if Rob did do the right thing and leave his cheating wife, then confronting Abby would leave Sienna with no leverage. There’d be no reason for Abby to tell her where Greg is because she’d have nothing left to protect. Her marriage would be over. Her life wrecked. This isn’t what Sienna wants. She just needs to find her husband.

If Abby won’t be honest with her, and Sienna has tried to get the truth, then she has no option but to push Abby to her limit. She is bound to crack eventually and see that talking to Sienna is her best option if she wants to preserve the life she has.

So this is why she is now standing outside Rob’s parents’ house, ready to plant a seed in their heads and see how it will grow. Another warning for Abby. A different one. More effective, she hopes.

Abby and Rob had been getting into their car when she’d turned up yesterday, so without any idea why she was doing it, she followed them. Before long it was clear that they were heading to Reading, and she knew Rob’s parents lived there. She hadn’t known last night what she’d do with this information; it is only now that she knows.

‘Can I help you?’ Lillian asks. This woman has to be Rob’s mother, the resemblance is clear. Sienna is pleased she took the trouble to put on full make-up this morning, and that her hair is freshly washed. She needs to make a good impression; this is one thing she’s good at.

‘Hi, I’m a friend of Rob and Abby’s and I was just wondering if you could spare a minute to chat?’

She holds her breath, waits for Rob’s mother to frown and tell Sienna she is busy. She couldn’t blame her if she does this; Sienna is fully aware that turning up on her doorstep like this is nothing short of strange.

The woman’s eyes narrow, suspicion clouding her expression, even though she appears friendly. ‘Oh? What’s happened? Is Rob okay?’ She flattens her hand against her chest.

‘Oh, yes, sorry, it’s nothing like that. I’m so sorry. Are you okay?’