At the café in the rabsad, Kaura was reviewing data from drinking-water samples.

 One of the samples—from a source in the former delta of the Pau River (Laura smiled, remembering how enthusiastically Auran had once described that canyon of a vanished stream)—showed a strange fraction.

Kaura frowned, trying to recall what that substance was. She had seen the formula long ago.

 “What is it? What?”

 The ecologist stared into her tablet so intently that she didn’t notice the investigative reporter Maush walking straight toward her.

He too was lost in thought, absorbed in his notes.

 Both moved quickly, driven by their inner rush—so of course they collided.

 The tablet flew from Kaura’s hands and landed at the feet of the man who had dropped onto his seat with a soft thud.

He picked it up, then himself, and handed the find back to its owner.

“Sorry!”

“No, my fault — I got distracted.”

“So did I,” the reporter laughed. “Don’t take this as nosiness, but what kind of data are you looking at? I saw a mention of my hometown and the dates — looks like post-catastrophe material. If it’s not classified, of course.”

“It’s not. These are open eco-monitoring records.”

“Still, there must be something unusual if it caught you like that.” He trusted his instinct — and it told him this was important.

“Yes. One of the samples contained a very rare fraction — extremely rare. It’s artificial, yet there’s nothing in the surrounding area that could’ve introduced it, even in case of damage…”

 She was speaking slower and slower, almost syllable by syllable, as her mind finally pulled up the forgotten memory — and she gasped.

 “I remember! I remember what it is… But—”

Her eyes drifted somewhere far away, unfocused, and her face grew troubled.

 “But that would make it even stranger…”

“Sorry, what’s your name?” Maush asked. He’d seen her around the rabsad and at a few conferences, but they’d never been introduced.

 “Kaura,” she answered automatically, still deep in thought.

 “And I’m Maush.”

 “I know,” she said with a gentle smile.

“Kaura, let me walk you out — you can tell me everything on the way? I can feel this matters!” the man said earnestly. “If it’s not for disclosure, I promise I won’t share a word without your consent. But I need to know”

 “Yes, I understand. You’re worried about your hometown,” Kaura nodded. She still wasn’t sure what to do with the realization that had surfaced, but something about this man inspired trust — and it felt important to share it with him.

They left the café and walked along the path toward her co-working dome.

 “You see,” Kaura began, “it’s one of the components of photon torpedo fuel… torpedoes that haven’t been used for nearly a century — not since the Last War.”

Photon torpedoes were a legacy of that war — guided munitions designed for orbital and stratospheric operations. Their fuel cartridges were known to be extremely unstable outside of regulated storage conditions.

“One might think that maybe parts of a rocket or fuel tanks, or other contaminated objects, remained down in the rock strata and then, shifted by the quake, met the water source,” Kaura said. “Only—here’s the catch: after so long that stuff should’ve broken down. It’s stable for a month, maybe a month and a half at most, and only under very strict conditions. I’m not a chemist — I know this by pure chance. Long story from my childhood,” she smiled, apologising for the possibly excessive intrigue around the sample.

“But don’t worry: it was found in just one out of the couple of hundred samples taken from that source, which means a vanishingly small amount got into the water. For now the intake from that spring has been suspended pending the test results; water is being diverted to a neutral zone.”

The Neutral zone — buffer reservoirs outside the main water supply system — was where questionable volumes were diverted until final analyses were complete.

 New samples would be taken before any release back into the city network.

“I see,” Maush said. “Thank you for sharing that. Is there anything else unusual showing up in the eco-monitoring data?”

“Not really,” Kaura admitted, “though to be honest, I haven’t been fully focused lately. I got distracted by other problems. My sister was hurt — she’s staying with me now… and there’s something else.”

She paused, remembering her strange experience at the Rings.

“Is Auran here?” she asked as they reached the right half-dome. Kaura turned to Maush to say goodbye — and at that moment, she saw it: the same glowing disk above his head that she had once seen above her sister’s.

“Could it be that this fuel — or one of its components — is used for something nowadays?”

 “Good thought! I haven’t heard of it being used anywhere else, in fact, I haven’t heard about it at all for ages. But I can’t say for sure. Like I said, I’m no chemist — nothing comes to mind yet, but that doesn’t mean it’s impossible. I’ll ask someone who might know.”

 “I can check too — I’ve got people to ask. Send me the info to my private mail, will you?”

 “Sure!”

They brought their wristbands close and exchanged virtual cards.

“Whoever solves the mystery first shares it with the other. Deal?”

 “Deal,” he agreed, amused by her curious spark. Nice girl, he thought, watching her silhouette fade into the half-dome’s gentle glow.

When Kaura disappeared behind the glass wall of her office, Maush remained standing for a while.

 Fragments swirled in his mind: photon-torpedo fuel, a substance that shouldn’t have survived… And then, suddenly, memories surfaced — the pink bottle, the deep imprints of heavy supports in the Pau canyon. In all the chaos and worry for his family, he’d nearly forgotten them. Now everything began to line up.

His intuition — the same one that had saved him more than once in investigations — gave a familiar tug: somewhere nearby was a thread worth pulling.