Kaoru scowled at her old friend. “If you’re going to make fun of me, I’ll just leave.”
“What have you learned about the helium tank that was found?” asked Yukawa, ignoring her threat.
“We know that it was being used in Kikuno Park on the day of the parade and we know what time it was stolen. The man who was looking after it had an alibi.”
“That sounds like a bounteous harvest to me. You don’t think so?”
Utsumi couldn’t suppress a sigh.
“Is there a witness who saw the tank being stolen? Are there any reports of a suspicious-looking person carrying a package or luggage big enough to hold the helium tank? Is there any useful footage on any of the nearby security cameras? I’ve been running around like mad since yesterday hunting for answers to all those questions. That’s what I’ve been doing since early this morning, too — with absolutely nothing to show for it.”
“I’m sorry to hear that. People started piling into the area early in the morning on the day of the parade to secure a good spot; the sidewalks were absolutely heaving. It’ll be like looking for the proverbial needle in a haystack,” Yukawa said.
“If that helium tank played a part in the crime, timing issues mean that the killer must have made use of a vehicle. There’s a major road he would have to cross to get from the park to the crime scene. There’s an N-System monitoring device on that particular intersection, so we’ve managed to identify all the vehicles that passed that way in the relevant time period, but...”
“You can’t find anyone who’s linked to the case?”
“Exactly. You talked about a ‘bounteous harvest,’ but I have the opposite impression. As far as I can see, finding that helium tank only served to knock the whole investigation off course.”
Yukawa crossed his arms on his chest and leaned back in his armchair. “That’s a serious allegation.”
“You think? Anyway, shall we keep it between the two of us?” said Utsumi, lowering her voice. “Did Kusanagi tell you where the helium tank was found?”
“He said something about a patch of weeds.”
“Yes, a patch of weeds only about sixty-five feet from the crime scene. Close enough to be within the radius of any police search. That helium tank was literally crying out to be found. Plus, there was Hasunuma’s hair. Plus, the tank had fingerprints on it that made it easy to work out when and where it was stolen. The whole thing strikes me as just a little too convenient. We then use this piece of physical evidence to work out the killer’s movements, and what do we end up with? The most likely suspects now have alibis that hold up perfectly.”
“I agree about keeping this between ourselves. I’m planning to drop in to Namiki-ya any day now.”
“Oh, sorry, Professor. The chief told me you’re one of the regulars there.”
“The vegetable takiawase is a culinary masterpiece,” Yukawa said. A dreamy look flitted across his face, then he was all business again. “What you’re saying is that the helium tank the police found was nothing more than a decoy designed to confuse the investigation?”
“I think it’s a very real possibility. My theory is that a different helium tank was in fact used, which was then disposed of somewhere else. But” — Utsumi cocked her head — “I still have my doubts about the method of killing. Why should the perpetrator be so obsessed with helium? What’s the point of such a fixation?”
“You’re wondering why he fetishized helium?” said Yukawa. Suddenly, he drew a breath sharply, then frowned, gazed off into the middle distance for a while, and finally expelled all the air in his lungs, slowly and loudly.
“Had an idea?” Utsumi asked.
“At the crime scene, there was a sheet on the floor with a mattress and a quilt on top. That’s where Hasunuma was lying.”
“I believe that’s right, yes. Does it mean something to you?”
Yukawa didn’t answer right away. He was looking down, deep in thought.
“Professor?” Utsumi said.
“Just wait a moment.” The physicist hushed her by holding up his hand, palm out.
After a minute or so, Yukawa looked up again.
“There’s something I want you to look into for me. Ask Forensics; they should be able to do it.”
“What is it?” Utsumi reached hastily for her notebook.
“It’s several things, in fact. I’ll go through them with you later. There’s something else I want to deal with first. Now, am I right in thinking that Kusanagi has made up his mind that the Hasunuma case is connected with Saori Namiki’s unnatural death and that he isn’t pursuing any other lines of inquiry?”
“Such as what?”
“Well, there’ve got to be other people who bore Hasunuma ill will. Take Kusanagi as an example: He’s got his own special feelings for Hasunuma.”
Utsumi realized what Yukawa was getting at.
“Because of the other unresolved case from twenty-three years ago... Let me have a look.” She flipped opened her notebook and found the victim’s name. “You’re talking about the family of Yuna Motohashi?”
“They’re a possibility.”
“Possible — but unlikely.”
“Why so?”
“Simple. Too much time has passed. Yes, the case was brutal and the court’s verdict was unconscionable. Her family had every right to feel embittered. But that strikes me as a very good reason for why, if they were planning to take revenge, they would have done so earlier. Why should they suddenly pick now as the right time for retribution?”
“We’d need to ask them that. They could have their reasons. Either way, I don’t think it’s smart to reject the possibility out of hand. Will you be informing Kusanagi of your visit here today?”
“Yes,” Utsumi replied. “I don’t want him to think I’m trying to keep it secret.”
“In that case, could you give him a message? Even if he doesn’t have much faith in my hunch, he should take a look at the victim’s family and any other people of interest in the Yuna Motohashi murder case. He may find a link to the present case. No, I guarantee that he will.”
Yukawa spoke with such force that Utsumi felt almost uncomfortable.
“Where does your sense of conviction come from, Professor Yukawa? How can you be so unequivocal?”
“The reason is—” Yukawa held up his index finger. “If my latest hypothesis is correct, then as things stand now, we’re only missing a single piece to complete the puzzle. And that piece must exist in the past.”
27
Hearing the sound of raucous laughter, Natsumi looked away from her phone and up at the television. A popular comedian was swimming in a dirty river. Natsumi had heard that this show, which featured different television personalities tackling a range of challenges, was very popular. She’d tuned in for the first time tonight, but it quickly bored her and she’d switched her attention to social media.
Glancing up at the clock, she saw that it was just before 8 P.M. At Namiki-ya, it was a time-hallowed custom to keep the television on even when the restaurant was empty. They didn’t want potential customers who looked in to get the impression that the place was lifeless. Typically, at this time of night, they would have the channel set to NHK, the national broadcaster. Now, because they didn’t want to watch the news, it was set to another channel. Crimes and disasters, even ones that didn’t involve them directly, were the last thing they wanted to hear about.
Customers had noticeably declined since Hasunuma’s death. A few people would wander in around seven o’clock, but otherwise the place was deserted. In the eyes of the public, the restaurant was run by murder suspects and people wanted to give it a wide berth. The Namikis could hardly put up a sign out front that said: EVERYONE HERE HAS AN ALIBI.