70-Year-old Yu Jiahao has been having the same dream recently and went to see a doctor. Finally, he found out that it was a dream of a lifetime. The happy childhood days are unforgettable dreams that will eventually pass away; the passion of youth is a fantasy that has quietly left; in the prime of life, unknowing love has already stopped by the side, which is a dream that always exists; he keeps dreaming but always ends in broken dreams... When he wakes up from the dream in old age, he regrets it...