‘ “My good sense would be lost to me”?’ Simon muttered.

‘I know. Look, here’s the second version, from the DIARY file. Which was created six days after the last changes were made to the “diary” file. After that, the “diary” file was opened many times-whenever the newer DIARY file was opened, in fact-but never changed again. She didn’t need to change it, did she? Because version two was a separate document.’

Simon took the piece of paper from Norman’s hand. This time, he allowed Norman to read the whole passage aloud.

‘“I need her not to be around in the evenings. Evenings! Anyone would think I meant from six until midnight or something extravagant like that. But no, I settle for a mere two and a half hours between eight thirty and eleven. I am physically unable to stay up any later than that, because every minute of my day is so exhausting. I run around like a slave on speed, a fake smile plastered to my face, saying things I don’t mean, never getting to eat, enthusing wildly over works of art that deserve to be chopped up and chucked in the bin. That’s my typical day- lucky me. That’s why the hours between half past eight and eleven must be inviolable, otherwise I will lose my sanity.”

‘She’s rewritten it, hasn’t she?’ said Norman. ‘A “mere two and a half hours”, “a slave on speed”-nice alliteration. And the “lucky me” at the end. She’s made it more readable. Wittier, also, and more bitter. It’s as if she read through her first attempt, found it to be devoid of tone and decided to… well, perk it up a bit. You can look at the whole thing if you want: the original and the rewrite. I can print both.’

‘Print the original out in full and get it to me as soon as possible. ’ Simon was on his way to the door. ‘We’ve got plenty of print-outs of the first diary file.’

‘You mean the second,’ Norman called after him. But Simon was gone.

Norman’s face drooped. Hoist by my own petard, he thought. He’d said it was Simon’s job to work out what it all meant, but he’d been looking forward to a bit of a discussion; he’d thought they might try to puzzle it out together. But, come to think of it, when he’d left the room, Simon Waterhouse hadn’t looked puzzled. Which was puzzling.

‘Why would a suicidal woman want to perk up the last desperate outpouring of her misery?’ Norman asked his captive audience of computer equipment. Like Simon Waterhouse, they offered no satisfactory response.

Simon bumped into Sam Kombothekra outside the CID room. ‘We’ve got a problem,’ said Sam. ‘Keith Harbard’s still in reception. His cab hasn’t turned up yet. When’s Jonathan Hey getting here?’

‘He didn’t say a time. He just said as soon as he could.’

‘Shit.’ Sam groaned, ran his hands through his hair. ‘This is all we need.’

‘What does it matter?’ Simon followed Sam as he sprinted down the corridor towards reception.

‘They’re friends. Harbard’ll ask Hey what he’s doing here, Hey’ll tell him we’ve called him in as an expert to help us at the eleventh hour, Harbard’ll say he’s supposed to be our expert.’

‘So? We get rid of Harbard as politely as possible.’

‘There’s no way Harbard’s going to leave without a fuss, allow himself to be usurped by a better expert-a man half his age. He’ll be straight on the phone to Superintendent Barrow, who doesn’t even know we’ve called Hey in!’

‘That’s Proust’s problem, not ours. Proust agreed to Hey coming in; he can explain it to Barrow.’

‘We should have gone to Cambridge. Why didn’t we go to Cambridge?’ Sam, using another of his wife Kate’s techniques, answered his own question. ‘Because you’d already invited Hey here, without checking with me or Proust or-’

‘Sam?’

‘What?’

‘Can you hear something?’

The raised voices grew louder as they ran. One raised voice: Harbard’s. Simon and Sam crashed through the double doors to reception.

‘Professions… Professors,’ said Sam, red-faced. Simon understood his nervousness. Personally, he felt oddly detached from the proceedings. He smiled at Jonathan Hey, who looked relieved to see him. Hey was eyeing Harbard anxiously. ‘Is there a mistake?’ he asked Simon. ‘Keith said you didn’t need me after all.’

‘Keith’s wrong.’

Harbard turned on Sam. ‘What’s going on? Aren’t I good enough any more? You send me on my way and call in my close friend and colleague without even telling me?’

‘Keith, I had no idea you hadn’t been told,’ said Hey, looking as uncomfortable as a schoolboy about to be caned by the headmaster. ‘Look, I really feel awkward about this.’ He looked at Simon, clearly hoping to be let off the hook. ‘As Keith says, we’re friends, and-’

Sam had recovered. ‘This way, Professor Hey,’ he said, leading Jonathan Hey out of reception, steering him by the shoulders so that he couldn’t decide to leave with Harbard as a gesture of solidarity. The doors banged shut behind them.

‘Six-six-three-eight-seven-zero,’ Simon told Harbard. ‘That’s the taxi number. If it doesn’t turn up in the next five minutes, give them a ring. Tell them to put it on our account.’

He turned his back on the irate professor and hurried after Sam and Jonathan Hey. He caught up with them halfway to meeting room one. ‘What did you say to him?’ Sam asked.

‘Oh, just smoothed his ruffled feathers and poured oil on troubled waters.’

‘Yeah, I bet.’

‘I hope you did, Simon.’ Hey sounded alarmed. ‘Poor Keith. I’d like to phone him as soon as possible, if that’s okay. I’m not happy about… the way this has happened. Couldn’t you have warned me, or…?’

‘Jonathan.’ Simon put a steadying hand on his arm. ‘I know Keith’s your mate and you don’t want to offend him, but this is more important. Four people are dead.’

Hey nodded. ‘Sorry,’ he said. ‘You know I’m happy to help if I can.’

‘You’ve been a big help to me already,’ Simon told him. ‘That’s why our DI’s looking forward to meeting you. Sergeant Kombothekra’ll tell you that Proust rarely looks forward to meeting anyone. Right, Sam?’

‘Well… um…’ Sam coughed to avoid having to reply. Bad form to take the piss out of your inspector in front of an outsider. Jonathan Hey looked back at Simon for reassurance. So did Sam. Simon considered how rare it was that people looked to him for comfort. Usually he unsettled those around him with an inner turbulence he found impossible to hide. Now, for once, there was no churning in his head. He hadn’t had a chance to tell Sam, hadn’t stuck around long enough to tell Norman Grace, but the last piece of the puzzle had fallen into place in Norman’s office a few minutes ago. Now he knew everything. Charlie would have to marry him. If I really want her to…

They arrived at meeting room one where Proust was waiting for them. The inspector sounded unnaturally courteous as he shook Jonathan Hey’s hand and said how pleased he was to meet him. He looked incongruous, standing beside a tray laden with tea, coffee, sugar, milk, cups and saucers and an impressive range of biscuits-probably an entire selection box. The tray was lined with one of those lacy-doily things that Simon had never known the proper name for. Had Proust asked for that? Had Sam? Simon had told them both that Hey was well-spoken, used to the luxuries provided by Whewell College, Cambridge.

‘Tea, Professor?’ said Proust. ‘Coffee?’

‘I don’t normally… oh, what the hell. I’ll have a coffee. Thanks. White, one sugar.’ Hey blushed. ‘Sorry to sound like a wuss. If I drink too much caffeine I have stomach problems, but one cup won’t hurt. Endless peppermint tea depresses you after a while.’

‘I’m a green tea man myself,’ said Proust. ‘But since there’s none here, I might risk a cup of builders’ finest. Sergeant? Waterhouse?’

Both nodded. Was Proust actually going to pour drinks for all four of them? Incredibly, it seemed he was. Simon watched as he put the milk in the cups first, then tea in three of them, sugar in one, coffee and sugar in the fourth. He knows Sam doesn’t take sugar and I do-he must have noticed, stored the information away. Simon felt a pang of affection for the Snowman.