Beneath the locust tree in an old alley, four-year-old Lin Wan meets Lu Shi. The boy slips a milk candy into her hand and says, “Next time you're unhappy, I'll come find you.” He becomes the only light in her childhood. But he's always like a gust of wind, appearing and disappearing without a trace, leaving behind only the promise, “I'll find you.”
They reunite at sixteen, and Lu Shi is now a young man. With hearts fluttering like the fizz of orange soda, they exchange silver rings engraved with their names as a pledge of love. Then the truth hits without warning: he has a terminal illness, will live to forty at most, and slips through time uncontrollably. Lin Wan doesn't back down. She only says, “I'll stay with you.” She doesn't yet know that she is already immortal, destined to wait alone through the ages.
As the people around her gradually pass away, Lin Wan's face remains forever twenty-five. She waits for a hundred years, keeping watch over the old alley. Lu Shi occasionally falls back through time, from leaning on a cane and coughing blood to sitting in a wheelchair and reading letters. The last time, he tells her, “Don't wait anymore,” and then vanishes without a trace.
Until, in the autumn of the hundredth year, a child's voice rings out at the mouth of the alley. A little boy in a blue school uniform runs over, holding half a milk candy. The red cord around his wrist looks just like the one young Lu Shi used to wear. “Miss, I dreamed you were crying and said you wanted to give me candy.”
It turns out that the century-long wait was never one-sided. Once, he protected her as she grew up; now it's her turn to watch over his childhood, waiting for a tender reunion as time turns back.
