Berlin runs on borrowed power. The lifts stay dead until midday, the hospitals share generators after dark, and Marcus Stone spends ten-hour shifts talking dying turbines into one more night.
At three in the morning, a page comes under his door. It is a drawing he made years ago, half of it swallowed by censor ink, with three words in blue pencil beneath the black bars.
You were right.
He was told to stop that work a long time ago, and he stopped. Following the note shows him what happens when somebody else doesn't. A warehouse on no lease. Machines that build their own replacements. His engine, three-quarters finished, sitting on a cradle in the dark.
The people who built it have run the numbers on the world outside. Every version, every assumption, millions of times over. They keep arriving at the same answer, and it is not one any government will say out loud.
They need him to finish the engine. Nothing else they have will get anyone off the ground.
He is not the only one who remembers his name. Someone else has spent years quietly buying scientists across Europe, and has never once had to ask twice.
All Marcus has is a scratched plastic phone with a single number in it, and three days to use it.
Make the call, and there is no version of his life where he goes back to the turbines.
Second Edition, revised and expanded.