'Who?'
He pointed to a single initial: V.
The letter could have meant Vale. It could have meant Victor. It could have meant a dozen other people. But it was the first indication that the missing report had been handled recently, and Nia felt the investigation move from speculation into something harder and more dangerous.
CHAPTER 04
THE ENGINEER WHO WOULD NOT SMILE
Yui Matsuda answered Nia's message from a hotel room with the curtains drawn. Her English was precise and brisk. 'We have eighteen minutes before my next call,' she said. 'Tell me what is verifiable.'
Nia described the printer note, the postponed test receipt, and the empty witness-signature field. She did not describe her theories. Yui waited through the pauses and asked only for dates and document identifiers. At the end, she said something that made Nia sit up straight.
'Our system shows the test was accepted without our resident engineer's witness signature.'
'Is that possible?'
'It is possible for software to display it. Whether it is permissible is another matter.'
Yui explained that the barrier contained two independent protections. One closed the main gates when dangerous tides approached. The other redirected inland runoff around the sealed gates so rainwater would not become trapped behind them. In a city that was already wet before the sea rose, the second protection was not an accessory. It was the difference between a shield and a dam facing the wrong direction.
The missing test concerned the second system during loss of external power. It had never been designed to run only on the main electrical grid. If the backup system failed, pressure sensors could continue sending reassuring signals even after flow through the bypass had stopped.
'What does that mean for Friday?' Nia asked.
'If they demonstrate a closure without resolving the condition, the crowd may see a successful gate and believe they have seen a successful flood barrier. Those are not the same thing.'
Yui hesitated. 'There is something else. I did not approve the English certificate that carries my name.'
Nia's pen stopped. 'Someone forged your signature?'
'I did not say that. A signature can be attached through a delegated approval system. The authority depends on the scope. We must establish facts before assigning motives.'
It was an answer Nia recognized from her own cautious conversations with Camila. Yui was not trying to sound impressive. She was trying to be accurate.
The two women arranged to meet at a public engineering library, where the original design documents could be reviewed without using Nia's revoked work account. Before ending the call, Yui asked how Nia had learned Japanese.
On the library table lay three translations of the same engineering heading. One came from the manufacturer's technical appendix, one from the public brochure, and one from the contractor's operating manual. The first was dense but accurate. The second was friendly but vague. The third had inherited a phrase from the brochure that belonged nowhere near a commissioning document. Nia marked the differences with colored tabs. Yui stared at the pages and said she wished engineers were trained to read translation histories the way they read revision histories. A changed adjective could alter expectations just as surely as a changed cable could alter current.
Nia noticed that Yui corrected herself readily when uncertain. The technical director could explain an intricate relay in a minute, yet she refused to guess at the meaning of an abbreviated signature field. Nia had met professionals who performed authority by never admitting doubt. Yui performed it by naming what evidence she needed next. At one point, she called a colleague, apologized for interrupting his dinner in another time zone, and asked him to inspect an old drawing rather than trust her recollection. Nia realized she could learn as much from that habit as from the engineering explanation itself.
'A scholarship and a lot of embarrassing mistakes.'
'Good. People who remember being wrong often notice what confident people ignore.'
By late afternoon, the library table was covered with diagrams. Yui explained valves, cable routes, and emergency sequences while Nia compared the bilingual instructions line by line. Their partnership developed with no ceremonial announcement. Each was strongest where the other lacked knowledge, and neither needed to pretend otherwise.
On page eighty-six, Nia found a footnote omitted from the public English manual. It required an independent observer to witness any simulated blackout before automated operation could begin. She highlighted the sentence and slid the book across the table. Yui examined it, then put a hand flat over the paper.
'That is the line,' she said. 'Without it, the final acceptance certificate can appear complete.'