Nika learned to recognise the sky in places where no one was looking for it. On the roof of the library, after dark, she would draw a map of the inner sky in a notebook. She combined window lights, aerials and fleeing satellites into her own constellations of choices. On this day, the wind smelled of dust and the clouds hung low, like a suspended decision. She ran each line with a tremor as she knew the lines were changing direction. That evening, the paper seemed to resist, as if afraid of a mistake. Ms Bogna, the librarian on the astronomy floor, slipped her the mysterious envelope without a word. Inside lay a stiff card that darkened as Nika breathed on it. An inscription flicked on the edge: Meet me tonight at midnight where the stairs don't reach. She added in pencil, half-joking: It's just an exercise in imagination if you want to pass it. On the back was a sketch of a staircase that ended in a white void. The staircase in their tenement remembered wars, floods and disappearing cassette shops. The metal smelled of rust and the lift shafts showed a splintered face in each floor. Beneath the fifth floor, Fabian, from class, was waiting, holding a similar card and a rust-coloured key. They slid the cards together; the lines scrambled, laying an arrow between the fifth and sixth floors. Where previously there had only been a mezzanine floor, a door as thin as a card appeared. The handle was cold and buzzed slightly, as if waiting for the result of an unknown test. Beyond the door stretched a corridor of dark air, seeded with sparkling, slow dust. The echo of their footsteps echoed twice, once from the front and once from their future. The cards suddenly heated up, spelling out the phrase: Enter boldly, but leave something that weighs you down. - What does one leave behind in a place that does not exist? - whispered Fabian without smiling. - 'Maybe a version of myself that I no longer need,' said Nika, but hesitated. The corridor split like a prism; the left smelled of rain, the right had the taste of burnt paper. From the left they heard Nika's laughter, exactly that of a day that never came. From the right, someone called out names, in a teacher's voice, but said them in reverse order. The light of the first spark went out without a puff of smoke, and the door behind them slammed shut deafeningly. Nika squeezed the card; the line flared, dividing into two paths, each with their name on it. - If we choose wrong, what do we lose? - She asked as something invisible took the first step.