This is a story about first love and their entanglement as they grow up.
A kidnapping incident led to the acquaintance of wealthy daughter Xia Ai and Luo Xingchen and Luo Yingyue in a remote mountain village. Three years passed by. When the relationship between the three became deeper and clearer, the Xia family who came to look for Xia Ai did something that changed the fate of the three.
Eight years later, when they met again, things they once thought they had forgotten were still vivid in their minds. Luo Yingyue, who suffered so much because of Xia Ai, resolutely gave up her own happiness and used everything around her to take revenge on Xia Ai.
When Xia Ai and Luo Xingchen met again, they had constant estrangements in their hearts due to various events in the past, and more misunderstandings also grew amidst Luo Yingyue's troubles.
Yesterday's stardust, yesterday's promise, yesterday's mountain village, yesterday's boy.
"Xiao Chun, I will protect you, until... I can no longer..."