“If this works,” Lena said, “we’ll never know if it was us or the echo.”

“We could just let Brussels loop,” muttered Lena, his former grad student, now a pale ghost in the doorway. She held a cold coffee cup like a holy relic. “Eternal Tuesday. Some cities deserve it.”

“We build a resonator,” Aris said, voice raw. “Tune it to the sliver’s own future decay. Catch the echo of a pulse that will exist in twelve hours, use it to seal the fracture now .”

Aris didn’t laugh. He was staring at the old lab clock. Not the atomic one—the analog one, with gears. It had been his father’s. A cheap, ticking relic from the before-times, when time was just something you waited for.

He threw the switch.

Tick.