‘We know that but how did she?’ Simon fired back at him. ‘What, did she type “date-rape drugs” into Google and take it from there? I can’t see it. How would she know how much to take?’

‘There’s no point speculating,’ said Proust briskly. ‘The computer chaps will tell us what Geraldine Bretherick did and didn’t do with her laptop.’

‘We also need them to tell us when that diary file was first opened,’ said Simon. ‘If it was created on the day she died, for example. In which case the dates at the top of the entries are fake.’

‘All this we shall find out in due course.’ Proust picked up his empty ‘World’s Greatest Grandad’ mug, dropped his mobile phone into it and glanced towards his office. He’d had enough. ‘What about Mr Bretherick’s missing suit, Sergeant?’

‘That’s my action,’ Sellers told him. ‘Lucky me-all the dry-cleaners within a thirty-mile radius of Corn Mill House.’

‘Charity shops as well,’ Kombothekra reminded him. ‘My wife sometimes takes my clothes and gives them to charity without telling me.’

‘Mine used to, until I made my displeasure known,’ said Proust. ‘Perfectly good jumpers she used to give away.’

‘And if we find out the suit wasn’t given to any dry-cleaner or charity shop? What then?’ asked Simon.

Proust sighed. ‘Then we’ll have an unsolved mystery of a missing suit. I hope you can hear how Secret Seven that sounds. The evidence will still point to Geraldine Bretherick being responsible for her own death and her daughter’s. I don’t like it any more than you do, but there’s not a lot I can do. We’re only following up the Oswald Mosley suit angle because it’s important to Mr Bretherick. Sorry if that leaves you feeling let down, Waterhouse.’ Proust took his empty mug and phone and headed for the small cubicle in the corner of the room, three sides of which were glass from waist height upwards. It looked like the lifts you sometimes saw on the outsides of buildings. The inspector went in, slamming the door behind him.

To avoid the sympathy in Kombothekra’s eyes, Simon turned to the whiteboard. He knew the wording of the Brethericks’ ten-year-anniversary cards by heart, but not Geraldine’s suicide note. There was something insubstantial about it, too slippery for his mind to latch on to. He read it again:

I’m so sorry. The last thing I want to do is cause any hurt or upset to anyone. I think it’s better if I don’t go into a long, detailed explanation-I don’t want to lie, and I don’t want to make things any worse. Please forgive me. I know it must seem as if I’m being dreadfully selfish, but I have to think about what’s best for Lucy. I’m really, truly sorry. Geraldine.

Superimposed over Geraldine’s words in Simon’s mind were the words of her friend, Cordy O’Hara: Geraldine was always planning, arranging, whipping out her diary. I saw her less than a week before she died and she was trying to persuade me and Oonagh to go to EuroDisney with her and Lucy next half-term.

Simon turned his back on Kombothekra, Sellers and Gibbs and headed for the Snowman’s cubicle. He hadn’t finished with him yet.

Proust looked up and smiled when Simon appeared in his office, as if he’d invited him. ‘Tell me something, Waterhouse,’ he said. ‘What do you make of DS Kombothekra? How are you finding working with him?’

‘He’s a good colleague. Fine.’

‘He’s replaced Sergeant Zailer and you can hardly bring yourself to look at him.’ Proust trumped Simon’s lie with the truth. ‘Kombothekra’s a good skipper.’

‘I know.’

‘Things change. You have to adjust.’

‘Yes, sir.’

‘You have to adjust,’ Proust repeated solemnly, examining his fingernails.

‘Have you ever heard of anyone writing their diary straight on to a computer? The file wasn’t even password-protected.’

‘Have you ever heard of anyone putting Tabasco sauce on spaghetti bolognese?’ Proust countered amicably.

‘No.’

‘My son-in-law does it.’

What could Simon say to that? ‘Really?’

‘I’m not trying to encourage you to take an interest in my son-in-law’s eating habits, Waterhouse. I’m making the point that whether you’ve heard of something or not heard of it is irrelevant.’

‘I know, sir, but-’

‘We’re living in the technological age. People do all sorts of things on their computers.’

Simon lowered himself into the only free chair. ‘People who kill themselves leave suicide notes. Or sometimes they don’t,’ he said. ‘They don’t leave suicide notes and diary entries to ram the point home. It’s overkill.’

‘I think you’ve hit upon the perfect word there, Waterhouse, to describe Geraldine Bretherick’s actions: overkill.’

‘The note and the diary are… they’re different voices,’ said Simon, frustrated. ‘The person who wrote the note doesn’t want to hurt anyone, wants to be forgiven. The diary-writer doesn’t care who gets hurt. We know the note’s Geraldine’s handwriting. I say that means she definitely didn’t write the nine diary entries.’

‘If you mention William Markes, Waterhouse…’

‘The voice in the diary is analytical, trying to understand and describe the experience of day-to-day misery as accurately as possible. Whereas the note-it’s just one platitude after another, the feeble voice of a feeble mind.’

Proust stroked his chin for a while. ‘So why didn’t that occur to your man William Markes?’ he asked eventually. ‘He’s faking Geraldine Bretherick’s diary-why didn’t he take the trouble to get the tone right? Is he also feeble-minded?’

‘Tone of voice is a subtle thing,’ said Simon. ‘Some people wouldn’t notice.’ Like Kombothekra. And Sellers and Gibbs. ‘There’s no mention of suicide in the suicide note, sir. Or of killing Lucy. And it’s not addressed to anyone. Wouldn’t she have written, “Dear Mark”?’

‘Don’t be dense, Waterhouse. How many times have you been called out to a body swinging from a beam? When I was a PC it used to happen every now and then. Some poor blighter who couldn’t take it any more. I’ve read my fair share of suicide notes and I’ve yet to read one that says, “I’m sorry I’m about to slit my wrists, please forgive me for committing suicide.” People tend to skirt round the gruesome details. They talk metaphorically about what they’re doing. As for “Dear Mark”-come on!’

‘What?’

‘She wrote the note to the world she was leaving behind, not only her husband. Her mother, her friends… Writing “Dear Mark” would have made it too hard, too specific-she’d have had to picture him alone, bereft…’ Proust frowned, waiting for Simon’s response. ‘Besides, there’s something you haven’t thought of: if William Markes was the killer, why would he allow us to find his name on the computer, plain as day? He wouldn’t.’

He’s trying to convince me.

‘I don’t understand you, Waterhouse. Why did you change your mind?’

‘Sir, I’ve never believed that Geraldine Bretherick-’

‘One minute Charlie Zailer’s the last person you’re interested in, the next you’re staring after her with your tongue hanging out every time she passes you in the corridor. What changed?’

Simon stared at the grey ribbed carpet, resenting the ambush. ‘Why did Geraldine Bretherick slit her wrists?’ he said stubbornly. ‘She had the GHB she’d bought. On the Internet. She’d given Lucy enough to make her pass out, so that she could drown her in a bath full of water without any fuss. Why not do the same when it came to killing herself?’

‘What if she botched it?’ said the Snowman. ‘Miscalculated, and woke up a few hours later-wet, naked and groggy-to a distraught husband and a dead daughter? I think you’d agree that Geraldine Bretherick’s wrists were slashed by someone whose intention was unambiguous. They cut downwards, not across. What do we say?’

‘But-’

‘No, Waterhouse. What do we say? Alliterate for me.’

‘Across for attention, down for death,’ Simon recited, feeling like the biggest idiot in the world. As he spoke, Proust pretended to be a conductor, waving an imaginary stick with one hand. Twat.