In 2005, newlywed Jiang Qianxi boards a bus home, telling her husband Gu Chi, “I’ll be back by dawn.” That night, her bus vanishes inside a tunnel. When she wakes, she has aged only ten hours—but the world outside has moved forward twenty-one years. She is still twenty-one. Gu Chi is forty-four, weathered and broken by a lifetime of waiting. Everyone else is gone. Her parents are dead. Her ID was cancelled in 2013, her family having filed a death report. The young husband she remembers has become a tired, injured man who deliberately pushes her away, too ashamed of his age and his failing body to let her love him. But she refuses to let go. Slowly, she breaks through his walls. They rebuild a life together, filling in the twenty-one years she missed. He teaches her the new world; she teaches him how to smile again. She gets pregnant. It looks like a hard-won happy ending. Then the truth shatters everything. There was no time slip. No miraculous return. Jiang Qianxi died in that tunnel in 2005, her body never found. Everything we watched—every reunion, every kiss, every tender moment—was a dream Gu Chi built in his final days, a fantasy conjured by a dying man who never stopped waiting. The bus wreckage is finally discovered, and with it, the remains of the woman he refused to let go of. Dawn came. But she never came back. He only dreamed she did.