After Lu An quit his job at the power grid, his life was intruded by Xia Hui, a girl who claimed to be from three hundred years in the future. In their daily bickering and adjustments, the two gradually uncovered the secret of Xia Hui's time travel and clues to the future world. In his dreams, Lu An frequently entered a desolate world after nuclear pollution and met A Xia, a survivor who looked similar to Xia Hui but had a very different personality. The two of them worked together to survive in the ruins, exploring the truth behind the collapse of human civilization and the hope of survival.