Su Yan (Huang Peijia) is a girl who seems lively and cheerful, but actually has some low self-esteem. Because she is unwilling to open her heart, she has had many misunderstandings and conflicts with her family and friends. Under the love and care of her boyfriend Lu Jinyu (Chen Xian), she decides to confide in her relatives and friends by email on the eve of her wedding, revealing all the hidden truths. This coded letter also opens up their memories of their youthful past, but a car accident comes unexpectedly at this time...