‘Well, with this and what Utsumi was talking about, it’s nice that we’re finally making a little progress,’ Kishitani said.
Kusanagi looked up. ‘What was Utsumi talking about?’
‘Some tidbit she got from Detective Galileo,’ Mamiya put in. ‘He’s having her reexamine the filter on the water line at the Mashiba house. They sent it to – what was that place?’
‘Spring-8,’ Kishitani said.
‘Right, that place. Yukawa specifically requested we get it tested there. I’d imagine Utsumi is running around Metropolitan right now putting that request together.’
Spring-8 was the name of a radiology facility in Hyogo Prefecture, the largest in the world. Its ability to detect even the most minute traces of material had made it a popular choice for delicate Forensics work; their role in the poisoned curry case had put it on the map.
‘So Yukawa thinks the poison was in the filter?’
‘According to what Utsumi was saying, yes.’
‘But I thought he was saying there was no way to—’ Kusanagi stopped himself short.
‘What?’ Mamiya raised an eyebrow.
‘Nothing. Just, I was supposed to meet with him later on. He said he’d hit upon a trick – maybe he meant a trick for getting poison into the filtration system?’
‘That seemed to be what Utsumi was indicating – that Yukawa had figured it out. But apparently, he wouldn’t tell her exactly what the trick was. He’s as stubborn as he is brilliant,’ Mamiya added, shaking his head.
‘He wouldn’t tell me how the trick works, either,’ Kusa -nagi said.
A wry smile spread across the chief’s face. ‘Well, since he’s helping us for free, I suppose we can’t complain. And if he’s going through all the trouble of calling you over there, he’s probably got some good advice for us. Go and hear him out.’
It was already past eight when Kusanagi arrived at the university. He called Yukawa as he stepped out of the taxi, but there was no answer. As he made his way across the campus he called again; after he’d let it ring several times, Yukawa finally picked up.
‘Sorry, I couldn’t hear the phone.’
‘You in the lab?’
‘No, the gym. You remember the place?’
‘How could I forget?’
Kusanagi turned off the phone and headed for the gym. Just inside the main gate of the university, a little off to the left, stood a grey building with an arched roof. Kusanagi had spent more time there than in his dorm back when he was in college. This was where he had met Yukawa. Then they both were fit and trim, but now the only one with an athletic figure was the professor.
When he made it to the athletic facility, a young man in a tracksuit came out of the front door, badminton racquet in hand. He nodded to Kusanagi as he passed. Inside, the detective found Yukawa sitting on a bench, putting on a windbreaker. Kusanagi glanced at the court and saw that the nets were up.
‘Now I finally understand why there are so many old professors. They get to use the university facilities as a free personal gym their whole lives.’
Yukawa looked up, unperturbed. ‘There’s nothing personal about it,’ he said. ‘I have to reserve my time on the courts just like everybody else. And I take issue with your basic premise that university professors live long lives. First of all, it takes a considerable amount of time and effort even to become a professor, which would suggest that one needs to meet a certain standard of health just to get the job. You’re confusing causes with results.’
Kusanagi gave a dry cough, and looked down at Yukawa over folded arms. ‘What did you want to talk about?’
‘Don’t be in such a rush. How about it?’ Yukawa said, offering a racquet to Kusanagi.
‘I didn’t come here to play games – badminton included.’
‘I applaud your dedication to your work,’ Yukawa said, ‘but I can’t help but notice that your waist size has grown by at least nine centimetres over the last several years – and that’s being generous. I’d have to theorize that walking around questioning people isn’t quite enough to keep you in shape.’
‘Well, when you put it that way …’ Kusanagi took off his jacket and grabbed the racquet.
The two took to the court, facing each other across the net for the first time in at least twenty years. Yet despite the time lapse everything was instantly familiar to Kusanagi: the feel of the racquet, the look of the nets, the squeak of the floor. But the flow of the game, the angles of racquet and shuttlecock didn’t come back so readily; and it was painfully clear to him that his stamina was sadly lacking. In less than ten minutes he was hunched over, breathing hard.
Kusanagi watched as Yukawa smashed the shuttlecock into the empty half of the court. He sat down on the floor. ‘Guess I’m getting old,’ he said. ‘Though I can still arm wrestle our young recruits to the floor, I’ll have you know.’
‘The kind of fast-twitch muscles you use in arm wrestling can grow weak with age and still spring back with a little training. But the slow muscles responsible for maintaining stamina aren’t so elastic. That includes the heart. I highly recommend regular training,’ Yukawa said matter-of-factly. His breathing was calm and even compared to Kusanagi’s ragged gasps.
Bastard, Kusanagi thought. Still sitting, Kusanagi leaned back against the wall. Yukawa pulled out a water bottle and poured some into the lid, which he offered to his friend. Kusanagi took a sip. It was a sports drink of some kind, and very cold.
‘It’s just like being back in school, huh? Except I’m completely out of shape.’
‘If you don’t keep at it, strength and technique will both weaken. I kept at it, you didn’t. That’s all.’
‘Is that supposed to make me feel better?’
‘No,’ Yukawa said, a curious look on his face. ‘Am I supposed to be trying to make you feel better?’
Kusanagi chuckled, picked himself off the floor, and then returned the bottle lid to the physicist. His face grew serious. ‘So you think the poison was in the filter?’
Yukawa nodded. ‘As I said on the phone, I can’t prove anything yet. But I’m pretty sure it was.’
‘You did some follow-up tests?’
‘I actually tried a test here at the university. We acquired four copies of the exact same filter, laced each with arsenous acid, rinsed them several times, and then tried to see if we could find any traces. Of course, with our lab here, we were restricted to induction-coupled plasma analysis.’
‘Induction-coupled what?’
‘It doesn’t matter. Just think of it as an extremely sensitive analytical method. We tested the four filters, and found clear traces in two of them, while the other two gave us insubstantial findings. A very special coating was used on that particular make of filter, making it extremely difficult for minute particles to adhere to the surface. According to Utsumi, Forensics used atomic absorption analysis on the Mashiba filter, which is an even less accurate method than the one I used. Thus, Spring-8.’
‘You must be pretty sure about this to go that far.’
‘I wouldn’t say I am absolutely sure, but it’s really the only option remaining.’
‘So how did the killer get the poison in there? I thought you said it was impossible.’
Yukawa fell silent. He was gripping his towel in both hands.
‘You think it is this trick of yours,’ Kusanagi said after a moment. ‘But you won’t tell me what it is.’
‘Like I told Utsumi, I don’t want to give either of you preconceived notions.’
‘Why would my preconceived notions have anything to do with the trick used to poison the filter?’
‘It has everything to do with it,’ Yukawa said, staring directly at the detective. ‘If the trick I’m thinking of was used, it’s highly likely that there will be some telltale trace remaining. That’s why I had the filter sent on to Spring-8, to find that trace. But even if they find no trace, it doesn’t prove that the trick wasn’t used. That’s the kind of problem we’re dealing with here.’