2040 Nanjing is full of green and has become the "big eyes of animals" heaven. Ban Xia insists on using radio stations to contact the world every day. In 2019, high school student Bai Yang became a radio enthusiast under his father's influence. When he made independent communication for the first time, he accidentally receives a signal from Ban Xia in 2040. The two embark on a communication journey across time and space.

　　2019年生活在南京的高三生白杨，意外通过无线电联络到了自称来自2040年的唯一幸存人类半夏，本不以为然的他在经历过无数次试验后，发现对方竟身处末日时代的南京！为挽回人类灭亡的厄运，他们就此展开了一场跨越时空的救援行动…… 　　影片改编自天瑞说符的同名科幻小说。