When her son is kidnapped, the inventor of a time machine teams up with multiple versions of her future self to rescue him.

The story revolves around Xia Tian, a single mother and an associate researcher whose life's work is a machine that can allow people to return to the past. However, upon the completion of the machine, her son, Dou Dou, gets kidnapped and is held ransom in exchange for it. The only way she can save her son is by using the machine to travel an hour and fifty minutes back in time to prevent the kidnapping.