Yukawa chuckled. ‘Don’t start jumping at shadows yet. Like I said, I’m only interested in this because it’s piqued my scientific curiosity. Which means, by the way, that should I lose interest, I’m out. That’s why I want you to let me into that house again. To make my final determination.’
The detective looked his friend directly in the eye. Yukawa looked back, cool as ever.
Kusanagi hadn’t the slightest idea what the physicist was thinking. This was nothing new. Kusanagi knew that there was a point when he just had to let go, and trust that Yukawa would come to the rescue as he had so many times before.
‘I’ll call Mrs Mashiba. Give me a second,’ he said, standing and pulling out his phone.
Going to a quiet corner, he dialled Ayane’s number, and when she answered he asked if it was all right for him to let himself in one more time. ‘I’m sorry to make this request yet again, but there was one last thing we really needed to check.’
He could hear her give a little sigh on the other side of the line. ‘You don’t need to check with me every time, you know,’ she said. ‘It’s an investigation; I expect you to be going in and out frequently. I hope you find something.’
‘Thanks. I’ll water the flowers while I’m there.’
‘Thank you so much. It’s a big help.’
Kusanagi went back to the table. Yukawa was looking up, observing him as he approached.
‘You got something to say?’
‘I was just wondering why you felt the need to get up in order to make the call?’ Yukawa asked. ‘Was there something you didn’t want me to hear?’
‘Of course not. All I did was get permission to go inside her house.’
‘Huh.’
‘What is it now?’ Kusanagi glared.
‘Oh, nothing. It’s just, when I watched you making the call, I couldn’t help but think you looked less like a detective, and more like a salesman making a pitch to an important customer. Is there some reason you have to tread lightly around this Mrs Mashiba?’
‘I was asking if we could go into her house. It’s a sensitive subject.’ Kusanagi picked up the bill from the table. ‘Let’s get going. It’s late already.’
They hailed a cab by the station. Sliding into the seat, Yukawa pulled out the magazine he had been reading in the café.
‘You were saying earlier that dinosaur fossils were all bones, but that assumption carries a considerable amount of risk. In fact, it’s an assumption that led many paleontologists to discard a lot of extremely valuable material.’
This again. ‘All of the dinosaur fossils I’ve seen at the museum were bones.’
‘That’s right. That’s because they threw out everything else.’
‘Everything else? Like what?’
‘Say you’re digging a hole and you find some dinosaur bones. Naturally, you get excited and dig them right up, brushing off all the dirt, so you can construct your big impressive dinosaur skeleton. Then you start making observations: “So that’s what a tyrannosaurus jaw looks like”, and “Look at those short forelimbs”. But, it turns out, you’ve already made a terrible error. In 2000, a certain research group dug up a chunk of dirt with some fossils in it and ran the whole thing through a CAT scan without cleaning it all. And guess what? They found the heart. The dirt trapped inside the skeleton had preserved the shape of the creature’s internal organs perfectly. These days, it’s standard practice to run a CAT scan on all fossils.’
Kusanagi grunted. ‘That’s pretty interesting, actually,’ he admitted. ‘I’m just not sure what it has to do with anything. Or were you just making small talk?’
‘When I first heard about the discovery, you know what I thought? I thought: here is a very clever trick, one that it took several millennia for Mother Nature to pull off. You can hardly blame the paleontologists who cleaned the dirt off the first dinosaur bones they discovered. But, as it turns out, the dirt they discarded as “useless” turned out to be extremely important.’ Yukawa closed the magazine. ‘You may have heard me mention the process of elimination, by which we invalidate one hypothesis at a time, eliminating all the possibilities until we’re left with a single truth. However, when there is a basic error in the way we form our hypotheses, that method can lead to extremely dangerous results. Sometimes, when we’re too eager to get those bones, we end up missing the point.’
So this conversation does have something to do with the investigation. ‘You think we made a mistake in our thinking about the route of entry for the poison?’
‘That’s what I’m going to go and check now. It’s just possible that our killer is quite the scientist,’ Yukawa added, half to himself.
The Mashiba residence was quiet and dark. Kusanagi retrieved the key from his pocket. He had already tried to return both copies of the key to Ayane, but she’d left him with one, saying that the investigators might still have need of it and as long as she didn’t have any plans to go home, it was no use to her.
‘The funeral’s over, isn’t it? No plans to do anything at the home?’ Yukawa asked as he was taking off his shoes.
‘She didn’t mention anything. The husband wasn’t a very religious man, so they did a flower ceremony in place of a formal funeral. There was a cremation, but none of the other usual observances.’
‘Sounds like a logical way to go about doing things. Maybe I should put in a request to receive the same treatment when I die.’
‘Fine by me,’ Kusanagi grunted. ‘I’d be happy to make the arrangements.’
Inside, Yukawa walked swiftly down the hallway. Kusanagi watched him go, then made his way up the stairs, opening the door to the master bedroom. He opened the sliding door that opened onto the balcony and picked up the large watering can on the other side – a purchase he had made at the home repair centre yesterday after Ayane asked him to water the flowers.
Can in hand, he went back downstairs. He found Yukawa in the kitchen, under the sink again.
‘Didn’t you check under there last time?’ he called out.
‘Aren’t you police always talking about fine-toothed combs? That’s all I’m doing,’ Yukawa countered. He was carefully examining the space by the light of a small penlight. ‘Oh well – no sign that anyone touched anything in here at all.’
‘Didn’t you check that last time?’
‘Yes, but I thought it might be prudent to go back to square one. We have the dinosaur fossil in front of us, all we have to do is avoid carelessly removing the dirt.’ Yukawa turned towards Kusanagi; a suspicious look came into his eyes as he caught sight of the object in the detective’s hand. ‘What’s that?’
‘Never seen a watering can before?’
‘Oh yeah, I seem to recall you sending Kishitani off to water the plants last time. Is this all part of a new PR campaign? “The police – we’re not just public servants, we’re servants”?’
‘Laugh it up,’ Kusanagi said, pushing past him to get to the sink. He placed the can under the tap and opened it all the way.
‘That’s an awfully big can,’ Yukawa noted. ‘Doesn’t she have a hose in the garden?’
‘This is for the flowers on the second floor. The balcony’s covered with planters.’
‘A policeman’s work is never done,’ Yukawa said, grinning, as Kusanagi headed out of the kitchen.
Back up on the second floor, Kusanagi began to water the flowers. Though he couldn’t have named a single one of them to save his life, even he could tell that the plants weren’t doing so well. Better not let them wilt. The watering complete, he shut the balcony door and hurried back through the bedroom. Even if he was here by permission, it didn’t feel right to linger in someone else’s sleeping quarters.