Aftertone A thousand years ago you could walk between worlds. Hundreds of them, connected by gateways — twenty metres of dressed stone, one ring inside another, standing in a wall or a courtyard or a hillside. Trade moved through them. So did people. Nobody thought it was remarkable, in the way nobody thinks a road is remarkable. Then, inside a single generation, every gateway went dark. Earth was cut off first, and worst. Long enough ago that nothing survived of it at all — no record, no story, no word

• Sci-fi