When Pwalu's wife Qesem came home from the village, nine months pregnant after only being gone for a few hours, he thought she'd simply fallen afoul of a time warp. Unfortunate, but understandable. The village midwife said she and the baby seemed healthy. But when the months dragged on and she never gave birth, he knew it was time to consult the scientist who lived in the ruins of a vast city hundreds of kilometers away.