Under this tirade someone had written in red pen: ‘No more in this vein please, Mummy. Amy gets upset when yet again she can’t read her weekend news out in class or enter it in the Busy Book. Please could you allow Amy to write her news book entries herself like all the other children instead of dictating your own words for her to write down? Thank you.’

‘Are you going to tell us what it is?’ asked Nick Thorning.

‘It’s just some child’s school book,’ said Esther.

Sam wanted to hit her. He looked at the next and final entry in the book. Unlike the other two, it contained some spelling mistakes.

This weekend I played with my friends and went to see Mungos Magic Show at the theata. It was great.

Under Amy’s handwriting there was a big, red tick. A teacher had written, ‘Sounds lovely, Amy!’

Whoever that teacher was, Sam wanted to hit her too.

You learn something new every day, thought Gibbs as he waited in Cordy O’Hara’s lounge for her to fetch Oonagh. Fine Art Banking. He’d spent half an hour on the phone to Leyland Carver before coming here, and found out that Encarna Oliva had been one of two people at the bank who had specialised in advising clients on which paintings, sculptures, installations and ‘conceptual pieces’ they ought to invest in. Gibbs hoped he’d done a good enough job of concealing his disgust. Couldn’t rich wankers choose their own pictures? What was the point in being alive if you hired someone to make every little decision for you?

Gibbs liked the idea that being rich made a person stupid. He also liked feeling aggrieved. He didn’t understand why-it was simply something he quite enjoyed. When he’d heard the salary Encarna Oliva had been paid to do her entirely unnecessary job, and that was before bonuses… Gibbs hoped Lionel Burroway of Leyland Carver wouldn’t ring and complain to anyone at the nick about Gibbs’ response when he’d been told the figure. ‘Ms Oliva worked extremely hard, and often long hours,’ Burroway had said defensively. ‘Most of the private views she had to attend were in the evening, and she often had to go abroad. Her work for us brought in ten, twenty times what we paid her in new business. She was excellent at her job.’

‘Right,’ Gibbs had grunted. That was a new one, the idea that a person’s work might actually bring in money. I’m in the wrong profession, he thought. All his work brought in was deviant scrotes that no one was pleased to see.

He had asked Burroway if Encarna Oliva had had a colleague called Patrick, perhaps a close friend. Burroway said he couldn’t recall there ever having been a Patrick at Leyland Carver. When Gibbs had mentioned that Encarna might have eloped with him to Spain, Burroway’s voice had cooled considerably. ‘The manner in which she left us was very odd,’ he said. ‘I would have preferred to be informed in person rather than by e-mail with no notice, but… well, I suppose if she’s…’

If she was murdered, you can’t hold a grudge against her for rudeness, Gibbs had thought, grinning. Even knowing Encarna was dead, Burroway had resented having to let her off the hook.

The music Cordy O’Hara had left playing was doing Gibbs’ head in. He got up, walked over to the small silver ghetto-blaster on the floor and turned down the volume ever so slightly. He examined the CD case that was balanced on top of the machine: The Trials of Van Occupanther by Midlake. Gibbs had never heard of it.

Large floor cushions, upholstered in bright, flowery materials that ought to have clashed but in fact looked all right, were strewn everywhere. They looked more expensive than Gibbs’ three-piece suite. Amid the cushions were pottery cups that also looked pricey and were probably hand-made, some with cigarette butts in them and ash streaks down the sides. A few screwed-up Rizlas and some empty takeaway cartons lay under the green glass table that stood in one corner. It was as if a group of homeless people had broken in and had a party in the home of an interior designer.

Cordy O’Hara had her hands on Oonagh’s shoulders as they came into the room, and a baby in a sling round her neck. Like a broken arm. ‘Sorry,’ she said. ‘Ianthe needed changing. And sorry about the mess. Since having baby number two, I’ve been forced to embrace squalor, I’m afraid-too knackered to clean the flat. Oonagh, this is Chris. He’s a policeman. Do you remember the other policeman, Sam? Chris works with Sam.’

Gibbs didn’t like the first-names thing-he hadn’t said Cordy O’Hara could call him Chris-but he said nothing. He did what Sellers would have done if he were here, and started by assuring Oonagh that there was nothing to worry about. She was only six, so he avoided referring to her having lied when Kombothekra interviewed her, and simply said, ‘Oonagh, you and Amy have been exchanging e-mails ever since she went to Spain, haven’t you?’ He shot Cordy O’Hara a warning look. She knew Amy was dead; Oonagh didn’t, and he didn’t want her to find out now. The girl tried to shrink into her mother’s skirt. Her round, wide-open eyes stared at the carpet. She was the image of her mother: thin, freckled face, carrot-coloured hair.

‘Her dad helped her type the messages,’ said Cordy. ‘When Oonagh said she hadn’t been in touch with Amy since Amy left school, I had no idea she was fibbing. Not until I spoke to Dermot.’

‘It doesn’t matter,’ said Gibbs. He hated situations that required him to be sensitive. ‘Oonagh, nobody’s angry with you. But I do need to ask you some questions. Do you remember, in one of your messages, asking if everything was all right between Amy and her mum?’

Oonagh nodded.

‘Did you have any reason to think things might not be okay between them?’

‘No.’ Her voice was almost inaudible.

‘Did you think it was strange that Amy never answered your questions about her mother?’

‘No.’

‘Oonagh, sweetie, you must tell Chris the truth.’

Gibbs was instantly suspicious. Cordy O’Hara shrugged an apology at him. ‘I’ve been trying to get it out of her. Amy used to ask her to keep lots of secrets. Didn’t she, sweetie?’ Oonagh wriggled, hopping from one foot to the other.

‘Oonagh, you’ll be helping Amy if you tell us,’ said Gibbs. ‘Whatever it is.’

‘Please may can I go to the toilet?’ the girl asked her mother.

Cordy nodded and Oonagh fled. ‘Come straight back, please, sweetie,’ Cordy called after her. ‘They taught her at school to say, “Please may…”, but I can’t seem to drum it into her that you don’t need to say “can” as well.’

‘If she won’t talk to me, see what you can do once I’ve gone,’ said Gibbs.

‘I’ve tried endlessly.’ Cordy tucked her hair behind her multiply pierced ears. ‘She thinks something dreadful happens to people who tell secrets; it’s infuriating. If I force the issue, she’ll make something up. Once, ages ago, I found her crying in bed in the middle of the night. She was distraught. Lucy Bretherick-she could be a bit of a madam, Lucy-she’d browbeaten Oonagh into telling her one of Amy’s secrets. Poor Oonagh was terrified Amy would find out, that she’d send a monster to attack her in the night.’

‘What was the secret?’ Gibbs asked.

‘I never got it out of her. Having told Lucy and felt awful about it, she was hardly going to compound her crime by telling me, poor little love.’

On the spot, Gibbs decided that if he and Debbie ever succeeded in having a child, rule number one would be no secrets from Mum and Dad. Ever.

‘I feel terrible,’ said Cordy. ‘I was relieved when Amy moved away. Once she was gone, Lucy and Oonagh became… well, normal little girls. But while it was the three of them…’ She shuddered. ‘I was a horrible coward. I’m totally ashamed of myself now. I should never have exposed Oonagh to scenes like that. No wonder she was traumatised, when Lucy hounded her until she couldn’t take it any more and told Amy’s secret.’