‘On the tape, Millar says himself this was not premeditated, that the idea of swapping the tablets just “came” to him,’ Miles said. ‘Besides, if he was as pissed as he says he was, I’d say he was surely much more likely to find Charlie, then punch his lights out.’

‘Whatever,’ sighed Jazz. ‘His entire confession has just been exploded.’

‘I was up at the school earlier and none of the boys remember seeing him upstairs on the sixth-form corridor. Sandwich?’ Miles pulled a plastic bag onto the table. ‘Egg and cress or a BLT, Ma’am?’

‘Neither, thanks. I’m not hungry,’ said Jazz. ‘Apparently, Millar did say he spoke to Hugh Daneman that night.’

‘That’s useful then.’ Miles bit into his BLT.

Jazz was still musing. ‘So, the question is: why is he lying? We know how much David Millar adores his son . . . and we know it was Rory who sought out his father on Sunday. What if he confessed to Daddy some involvement with Charlie’s death during their trip?’

Miles studied his sandwich. ‘And Daddy decides he must take the rap. We’ve seen that one before.’

‘And Rory was issued with two painkillers at nine that night. The drug sheet records they were paracetamol tablets, but something written beneath it had been Tippexed out. I’m waiting to hear from forensics to see what.’

Miles aimed the empty sandwich wrapper at the bin, and missed. ‘So, if by any chance we were to find the word “aspirin” has been Tippexed out and replaced with the word “paracetamol”, Rory not only had the motive, he had the wherewithal.’

Jazz paused. ‘It’s a pretty big thing to accuse a thirteen-year-old boy of murder.’

‘Yep, and, if he was involved, it also means someone in the school knows it and Tippexed the offending word out to protect him.’

‘Unless he did it himself,’ Jazz said quietly.

‘The drug sheet is kept inside the medicine cabinet, which is locked at all times. The only people with the key are Frederiks, Matron and, of course, Hugh Daneman on that particular evening.’

‘Why on earth did he have to top himself?’ Jazz sighed.

‘Maybe he was involved in some way with what happened.’ Miles shrugged. ‘We know Rory’s motive, but why would an adult, for example Hugh Daneman, try to protect him?’

‘Unfortunately, this is all supposition until forensics get back to us. Christ! This case is moving slowly.’ Jazz tapped her pen irritably on the table.

‘That’s the sticks for you, Ma’am.’ Miles grinned. ‘Do us both good. We’ll get back to London and appreciate what we have there.’

‘You might, Miles, I certainly won’t,’ Jazz replied sharply.

He swiftly changed the subject. ‘So, what was your instinct on Rory when you met him?’

‘I didn’t have a chance to get a feeling in the time I had. He was holding back on me, but that could have been for many different reasons. I’d mark him down as “odd”, I suppose, but then most teenage boys are strange. It doesn’t mean they’re killers.’