Salvation of a Saint

THIRTY

Hiromi Wakayama was already there when Kusanagi arrived at the café. He hurried over to the table.

‘Sorry to keep you waiting.’

‘I just got here myself,’ she told him.

‘Well, thanks for coming out. I’ll keep this as short as possible.’

‘Don’t worry on my account,’ Hiromi told him with a soft chuckle. ‘I’m not working right now, so I have plenty of time.’

Her complexion seems to have improved, Kusanagi thought. Back up on her emotional feet, maybe.

A waitress came to hover by their table, so Kusanagi ordered coffee. ‘Milk for you?’ he asked Hiromi.

‘Lemon tea, please,’ she said.

The waitress left and Kusanagi smiled. ‘Sorry. I just remembered you ordering milk last time …’

‘Actually, I’m not really a big fan of milk. And I’m trying to avoid it right now.’

‘Really? Why is that?’

Hiromi lifted an eyebrow. ‘Do I need to answer every question?’

‘No.’ Kusanagi waved his hand. ‘Of course not. Sorry, I was just making small talk. I’ll get down to business. The real question I have for you is about the Mashibas’ kitchen, actually. Do you remember that they had a water filter attachment on their sink?’

‘Sure.’

‘Did you ever use it?’

‘Never,’ Hiromi said without a moment’s hesitation.

‘That was quick,’ Kusanagi observed. ‘I mean, that’s the sort of question people usually have to think about a bit.’

She shook her head. ‘I barely even went into their kitchen. I never helped cook. Why would I touch the sink? I think I told detective Utsumi this, too, but the only time I ever went into the kitchen was to put on coffee or tea when Ayane asked me to, and that was only when she was in the middle of preparing something else and didn’t have time.’

‘So, is it true then that you were never in the kitchen alone?’

Hiromi frowned. ‘I’m not really sure what you’re getting at.’

‘I just need to know if you were ever in the kitchen by yourself. Don’t worry about why. Try to remember for me.’

Hiromi thought about it until wrinkles formed across her brow. Eventually she looked back up at Kusanagi. ‘Maybe not. I always had the feeling I wasn’t welcome in there without Ayane’s permission.’

‘Did she specifically tell you not to go in without permission?’

‘Not in so many words, no. It was just a feeling I had. And – you know, the whole thing about a housewife’s kitchen being her castle.’

‘So they say.’

The drinks arrived. Hiromi squeezed her lemon wedge over her tea and sipped at it, a smile on her face. She looked more alive than Kusanagi had ever seen her.

Certainly more alive than I feel. Everything she was telling him backed up Yukawa’s story.

He took a sip of his coffee and rose from the table. ‘Thanks again for your help.’

Hiromi’s eyes went wide. ‘That’s all?’

‘I’ve heard what I needed to. Take your time,’ he said, picking up the bill and heading for the door.

He was out on the street, looking for a taxi, when his phone rang. It was Yukawa. The physicist said he had something to tell Kusanagi about the poisoner’s trick.

‘I need to check something, urgently. Can you meet?’

‘Sure, I’ll come right over. But what do you need to check at this point? I thought you were pretty confident about your theory.’

‘I am confident. That’s why I need you to come as quickly as you can,’ Yukawa said, and hung up.

About thirty minutes later, Kusanagi was walking through the front gate of Imperial University.

‘When I started reflecting back on the case, with the assumption that Ayane Mashiba used the trick I described, something kept bothering me – and I thought it might be useful to your investigation,’ Yukawa said as soon as the detective entered the room.

‘Sounds important.’

‘Very. What I need to ask you is this: what did Ayane do first when she returned home after the murder? You were with her at the time, correct?’

‘That’s right. Utsumi and I gave her a ride home.’

‘What was the first thing she did when she walked in the door?’ Yukawa asked.

‘The first thing? Well, she took a look at the scene—’

Yukawa shook his head. ‘No. She went into the kitchen. She went into the kitchen to get water. Am I right?’

Kusanagi gaped. The moment played out again in his memory. ‘Actually, you’re right. She did go to get water.’

‘What did she get water for? She would need a particularly large amount, if my theory is correct,’ Yukawa added, a twinkle in his eye.

‘She watered her flowers. Said something about how it bothered her that they were all wilted. She put water in a bucket, and took it upstairs to water the plants on the second-floor balcony.’

‘That’s it!’ Yukawa said, pointing at Kusanagi. ‘That completes the trick.’

Kusanagi frowned. ‘I think I know what you’re getting at, but explain it to me anyway.’

‘You see,’ Yukawa began, ‘I tried thinking as the killer would think. She knew there was poison in the filter when she left the house. And, as she had hoped, her target drank the water and died. But that’s not enough. There could still be poison left over in the filter.’

Kusanagi straightened his back. ‘That’s true.’

‘It would be dangerous to leave it like that. If someone happened to drink it, she might have another body on her hands. Not to mention it would tip the police off to her trick. So she would have to find a way to destroy the evidence as quickly as possible.’

‘So she watered her flowers …’

‘With water from the filter, no doubt. A bucketful would be enough to nearly completely wash the poison out of the system. So much so that, without a lab as precise as Spring-8, we never would’ve been able to detect it. She was going on about her flowers, and destroying the evidence right in front of your noses.’

‘So that water –’ Kusanagi began.

‘– is your evidence, if there’s any left,’ Yukawa finished. ‘Even if finding trace particles of arsenous acid in the water filter isn’t enough to prove how she did it, proving that a deadly amount of arsenous acid had come out of that water filter on the day of Mr Mashiba’s death would probably be enough to prove my theory.’

‘I just told you, she used the water on her flowers.’

‘Then check the soil in the planters. I’m sure Spring-8 wouldn’t have any trouble finding arsenous acid if it’s in there. Though it might be difficult to prove that it came from the water she used at that time, at least it’s another piece of evidence.’

While he listened to Yukawa talk, something was tugging at the back of Kusanagi’s mind – something he couldn’t remember, something he’d forgotten that he even knew.

Suddenly it dislodged itself from the depths of his brain. Kusanagi gasped. He looked intently at Yukawa.

Yukawa stared back at him. ‘What? Is there something on my face?’

Kusanagi shook his head. ‘I need a favour. Actually, consider it a formal request from the Metropolitan Police Department’s Criminal Investigation Section to Imperial University’s Professor Manabu Yukawa.’

A hard look came over Yukawa’s face. He adjusted his glasses with the tip of a finger. ‘Go on.’