In the ruins of Neo-Mumbai, scavenger Leo uncovers an impossible relic: an ancient rotary telephone that rings with a desperate voice from exactly 24 hours in the past. On the other end is Kabir, an engineer trapped inside a failing thermal core minutes before it explodes. Racing against a fracturing timeline, Leo must guide Kabir through a burning maze of corporate sabotage to prevent the apocalypse that already destroyed his home. Can they change the past, or is the concrete of time set in stone?