‘Sorry to bother you when you’re busy. But there is something I have to tell you.’
‘Yes?’ Kusanagi gripped his phone tightly.
‘Finding poison in the kettle doesn’t necessarily mean that somebody actually put poison in the kettle.’
Kusanagi was flustered again. ‘Why’s that?’
‘Well, perhaps I should’ve mentioned this earlier, but my husband was extremely health conscious, and never drank water straight from the tap. Even when cooking, I always used water from a filter. He only ever drank bottled water, and he asked me to use it when I made coffee, too. I’m sure he used water from a bottle on Sunday.’
‘So you think the poison could have been in the bottled water?’
At the desk next to him, he saw one of Utsumi’s eyebrows go up.
‘I just thought that it might be a possibility. It just doesn’t make sense for Hiromi to have done it. And if the poison was in the bottled water, somebody else could’ve done it. Anyone.’
‘Well, that’s true, but …’
‘For instance,’ Ayane went on, ‘it could even have been me.’
ELEVEN
It was just past eight o’clock when Utsumi drove Hiromi Wakayama home. Hiromi had been in the interrogation room for only two hours, far less than Mamiya had anticipated.
Ayane Mashiba’s call was the main reason he’d cut off the questioning. The widow was very clear about her husband’s instructions: the dead man had insisted that bottled water be used exclusively for all coffee making. If that was true, then all the killer had to do was poison one of the bottles ahead of time – which meant Hiromi Wakayama was no longer the only suspect.
In any case, Mamiya had been unable to press her into making a confession. After two hours of the young woman’s tearful professions of innocence, he nodded with reluctant resignation when Utsumi suggested sending Ms Wakayama home for the time being.
Now she sat in the passenger seat, emphatically silent. She’s probably exhausted, Utsumi thought. She had seen strong men wilt under the heat of the hard-faced detective’s interrogations. It would take a while for the tears to fade from Hiromi’s eyes. Utsumi settled in for a quiet ride. Her passenger was too worked up to say anything. And why would she, anyhow, when she knew that she was now a suspect?
Hiromi’s mobile phone rang. She pulled it out of her handbag.
‘Yes?’ she said in a quiet voice. ‘We just finished. I’m getting a ride back now … No, the lady detective … No, not the station in Meguro, the Metropolitan Police Department. It might take a little longer to get home … Yes, thank you.’
She ended the call.
Utsumi took a few steady breaths, then asked, ‘Was that Mrs Mashiba?’
She could feel Hiromi tense in her seat. ‘Yes. Is there a problem?’
‘She called Kusanagi while you were being questioned. She seems very worried about you.’
‘She is.’
‘You talked about your relationship with Mr Mashiba?’
‘Where did you hear that?’
‘Mrs Mashiba told Kusanagi when he came to bring you down to the department.’
Hiromi fell silent, and Utsumi stole a glance at her. Her eyes were downcast, lips curled into a thin frown.
‘I don’t mean to be rude,’ Utsumi went on, ‘but it’s very strange to me that the two of you remain so close, when most people in your situation would be at each other’s throats.’
‘Well, he is dead.’
‘Still, it’s strange.’
There was a pause before Hiromi nodded. ‘I guess it is.’
She doesn’t understand it herself, Utsumi realized. She waited several seconds before she spoke again. ‘Actually, there are two or three things I wanted to ask, if you don’t mind.’
Hiromi sighed. ‘What else could you possibly need to know?’
‘I know you’re tired, and I’m sorry, but these are very simple questions. And the last thing I want to do is cause you any pain.’
‘It’s a little late for that. What did you want to ask?’
‘On Sunday morning, you and Mr Mashiba drank coffee, correct? And you made the coffee?’
‘That again?’ Hiromi asked, tears in her voice. ‘I didn’t do anything. I don’t know anything about any poison.’
‘I’m not asking about that, just about how you made the coffee. Do you remember what water you used?’
Hiromi blinked. ‘Excuse me?’
‘Did you use water from one of the plastic bottles in the fridge, or water from the tap?’
‘From the tap.’ Hiromi sighed again.
‘Are you sure?’
‘Yes. Why does it matter?’
‘Why did you use water from the tap?’
‘I didn’t have any deep reason, if that’s what you’re suggesting. I just thought using hot water would make it boil quicker.’
‘Was Mr Mashiba there when you made the coffee that time?’
‘He was. Didn’t I already say this a few times? I taught him how to make coffee.’ There was an echo of irritation through the tears in her voice.
‘Try to recall the moment as clearly as you can. I don’t mean when you were making the coffee, I mean when you were pouring water into the kettle. Was Mr Mashiba standing there?’
Hiromi fell silent, and Utsumi knew that this wasn’t one of the questions Mamiya had asked her.
‘Oh,’ she whispered after a few moments had passed. ‘You’re right. He wasn’t in the room yet when I put the kettle on. I’d just turned up the burner when he came in to the kitchen and asked me to show him how it was done.’
‘You’re sure?’
‘Yes, very sure.’
Utsumi pulled over and stopped the car. She put on the hazard lights and turned to face Hiromi directly.
‘What is it?’ she asked, shrinking away from the detective.
‘Ayane taught you how to make coffee at her house, yes?’
Hiromi nodded.
‘Well, Ayane told Kusanagi that her husband was very health conscious, and never drank water directly from the tap. Mr Mashiba had insisted that she always use bottled purified water, even for making coffee. Were you aware of that?’
Hiromi’s eyes went wide and she blinked. ‘She did tell me about that. But she said not to worry about it too much.’
‘Oh?’
‘Yes. She didn’t think it was very economical to use so much bottled water, and besides it takes longer to boil that way. But she told me if Mr Mashiba ever asked, I was to tell him I had been using bottled water.’ Hiromi put a hand to her cheek. ‘I completely forgot about all that!’
‘So Ayane was using tap water, too?’
‘Probably.’ Hiromi looked into Utsumi’s eyes. ‘It didn’t even occur to me to mention it when I was talking to the other detectives.’
Utsumi nodded, smiling. ‘It’s okay. Thank you.’ She turned off the hazard lights and released the brake.
‘Could you tell me why it matters?’ Hiromi asked. ‘Was there a problem with me using water from the tap?’
‘Not a problem. But, since there’s reason to suspect that Yoshitaka Mashiba was poisoned, we need to make sure we know every detail about what he ate on the day he died.’
‘I see …’ Hiromi lowered her gaze, then looked back up at the detective. ‘Ms Utsumi, you have to believe me. I really didn’t do anything.’
Utsumi swallowed, her eyes on the road. She was about to say I believe you, but instead she told her, ‘You’re not the only suspect in this case. In fact, at this point, we have to suspect everyone in the world. If anyone ever told you police work was fun, they lied.’
Hiromi fell silent.
Not the answer she was expecting.
Utsumi stopped her car by Gakugei Daigaku station, not far from Hiromi’s apartment. She watched as Hiromi got out and walked towards the apartment building. Then Utsumi glanced at the building itself, quickly turned off the engine, and got out of the car. Ayane Mashiba was waiting just inside the glass front door of Hiromi’s apartment building.