He climbed the stairs to the lounge. Nick Thorning was sitting on the sofa with Esther Taylor beside him, holding his hand. Whether he wants it to be held or not, thought Sam. Simon and Charlie sat in armchairs across the room.

‘What’s going on?’ Thorning’s eyes lit up when he saw Sam. ‘Is there any news?’

‘I phoned the credit card company and then the hotel.’ Sam tried to find a patch of carpet to stand on that wasn’t occupied by a newspaper, a crayon, a bib or a nappy. ‘Esther’s right: it was Seddon Hall in York. Sally stayed there between the second and the ninth of June last year.’ Sam nodded at Simon, who had raised an enquiring eyebrow. Yes: the second name he’d given the receptionist had also checked out, same dates. Simon looked relieved, then a little bit stunned. It was the way he always looked when he was proved right. Sam tried not to think about how often Simon turned out to be right. He might be tempted to resign if he allowed himself to dwell on it.

‘Don’t take it personally, Nick.’ Esther stroked his hand with a rhythmic ferocity that looked likely to remove layers of skin. ‘She needed a break, that’s all. When the work thing fell through, she… I mean, she did it more for you and the kids than for herself.’ Esther looked round the room, trying to garner support for her claim. ‘She’d reached her limit. She needed a break in order to carry on. Don’t any of your wives work?’ She stared defiantly at Sam and Simon.

Kate, Sam’s wife, didn’t. And she was still more tired than Sam at the end of every day; he wasn’t entirely sure why.

‘DC Waterhouse’s wife works full-time,’ said Charlie. ‘But then, they haven’t got kids.’

Sam couldn’t bring himself to give her the look he knew he ought to give her. He knew she was angry that she’d been sent to collect Esther Taylor from Rawndesley-like a skivvy, she probably thought-and angrier still that there hadn’t been time to bring her up to speed.

‘Is Sally’s life so terrible?’ Nick asked quietly. ‘I thought she was happy with me and the kids.’

‘She is,’ Esther insisted.

‘If she needed a break, why didn’t she say so?’

Simon cleared his throat. ‘Miss Taylor, what exactly did Sally say about meeting this man at Seddon Hall?’

‘I told you. One night in the bar, they got talking. He pretended to be Mark Bretherick, who also lives in Spilling, so they had that in common-or Sally thought they had, rather-so they chatted for a while about… you know, local landmarks.’

‘Local landmarks?’ This sounded odd to Sam. ‘Like what?’

‘Um… well, I don’t know exactly. I live in Rawndesley, and I’m from Manchester originally, but-’

‘The memorial cross?’ Simon suggested. ‘The old stocks?’

‘I don’t mean landmarks exactly. They just talked about… local stuff.’

‘Just the once, did they talk?’

‘No.’ Esther seemed more confident now. ‘He was there all week. Sally kept bumping into him: in the bar, the spa… I think they chatted a few times.’

Sam was growing increasingly certain that Sally Thorning had done more than bump into the man they now believed had murdered four people. If some sort of sexual liaison had taken place, chances were Esther knew about it and Nick Thorning didn’t. And Esther was determined to protect her friend’s secret. It doesn’t matter, thought Sam. What mattered was finding Sally, making an arrest before anyone else got hurt. Sellers and Gibbs might already have done both; Sam hoped to God they had.

‘Sally didn’t tell me either,’ Esther was assuring Nick. ‘Not for ages. Only when all this stuff about the Brethericks was on the news.’

‘Yeah, and then she told you! She should have told me. I’m her husband.’ Nick Thorning looked around the room as if hoping for confirmation from somebody.

‘She didn’t want to worry you.’

‘She’ll be okay, won’t she?’

‘Have you seen this?’ Sam held the envelope in front of Nick’s face.

‘Yeah, this morning. What about it?’

So it meant nothing to him. Was that a good sign? ‘It’s addressed to Esther,’ said Sam.

‘I know.’

‘Esther doesn’t live here.’

‘What?’ Esther craned her neck to see the writing on the envelope. ‘It’s addressed to me?’

‘I know Esther doesn’t live here,’ said Nick angrily. ‘I’m not stupid. I assumed Sally would know what it was and sort it out when she got back. I just want her to come back. She will, won’t she?’

‘We’re doing everything we can to find her and bring her safely home,’ Sam told him. ‘Esther, would you mind opening this?’

She tore open the envelope and pulled out a small green book, A6 size, and a postcard. ‘I’ve no idea…’ She looked up at Sam, frustration all over her face. ‘It’s addressed to me, but I haven’t got a clue what it is or what it means.’

Sam was afraid he’d be equally at a loss, and was pleased to find he understood straight away. He recognised the name Sian Toms-she was a teaching assistant at St Swithun’s. Sally Thorning had called herself Esther Taylor when she’d visited the school, but she must have given Sian Toms her real address.

‘Dear Esther,’ the postcard said. ‘Here is Amy Oliva’s news book, the one I mentioned when we spoke. Please don’t tell anyone I sent it to you-it would go down very badly at work. Also, please can you send it back to me when you’ve read it so that I can put it back? Thanks. Send it to my home address: Flat 33, Syree Court, 27 Lady Road, Spilling. Best wishes, Sian Toms.’

Sam opened the news book. The first entry was dated 15 September 2005, close to the beginning of the school year that was to be Amy’s last at St Swithun’s. The handwriting was Amy’s, or rather, it was clearly a child’s: large and unwieldy. When Sam began to read the words, a shiver rippled through him.

This weekend, Mum, Dad and I went to Alton Towers. After hours of queuing, we went on the Log Flume, which was mediocre. There was a ride called the Black Hole that I was keen to go on, but Mum said I was too young and it was only for grown-ups. I asked her if she and Dad wanted to go on it and she said, ‘We don’t need to. Dad and I are already in a black hole. It’s called parenthood.’

Sam turned to the next entry. The handwriting was the same but it was much longer.

This weekend was excellent. I ate nothing but chocolate-buttons, Minstrels, Milky Ways. For breakfast, lunch and supper. I was sick on Sunday afternoon, but on balance I think it was worth it. On Friday evening I was feeling more contrary than usual (those who know me well will scarcely be able to imagine such a thing) so I asked Mum if I could throw the horrid, healthy part of my tea-the part she had carefully home-cooked then saved and frozen in a small, purple plastic bowl-in the bin and instead go straight to the reward I normally only get if I eat lots of vile green things. To my surprise and delight, she said, ‘You know what, Amy? You can do exactly what you like this weekend, all weekend, as long as I can too. Do we have a deal?’ Of course I said yes, so she pulled all the chocolate out of the treat cupboard and threw it into my lap, and then she went and found a book she wanted to read. I asked her to put on my ‘Annie’ DVD for me, but she reminded me that we were both doing exactly what we wanted, and getting out of her chair to fiddle with the DVD player was not something she wanted to do. She also didn’t want to do any drawing, baking, jigsaws, hair-styling, or have her house littered with squealing, pink-clad Barbie-obsessed munchkins like Oonagh and Lucy. Fair enough! Actually, her quite reasonable refusal led to a valuable insight on my part. Sometimes, I ask Mum to do things-for example to get me drinks I then don’t drink, and toys and games I have no real desire to play with-not because I actually want whatever it is I’m asking for, but simply for the sake of making her do something, because I believe her role in life is to attend to my wishes. If she isn’t waiting on me like a maid, something seems amiss. All Western children are the same, Mum says, because society overprotects and over-indulges them. That’s why she makes a point of buying the produce, whatever it might be, of any company she hears has been using child labour. I have to admit, she’s got a point. If I swept chimneys or sewed clothes in a factory from dawn until dusk, I would certainly understand that after a hard day’s work, the last thing a person wants is to be given more work at home.