On his 18th birthday, Jan Wen shoots randomly at the crowds in a night market for unknown reasons. The tragic incident causes a strong impact on the lives of his family and friends, the victims and the witnesses. However, if there was a chance for them to make different choices, would the tragedy still happen? Will it be a different outcome if they all changed their behaviour at the crucial moment?

Ann and Mimi come across A-kai, a guy waiting for a mysterious on-call work. They hit it off right away. Yet, not getting what they want, they end up getting involved in a crime due to circumstances beyond their control.

On a cold Valentine's Day, a girl Xiao-Hua runs into a boy A-Wen who is waiting for his lover. Out of empathy, Xiao-Hua hands A-Wen a cup of hot milk tea. The two get to know each other since. On the same day, Zi-Jie Huang also bumps into Xiao-Hua. Zi-Jie behaves like a jolly charming womanizer, which makes Xiao-Hua uncomfortable. There are already frictions between the two at the first sight. Xiao-Hua is convinced that A-Wen's lover must be Yi-Chun, known as Butterfly. Out of surprise Xiao-Hua discovers Yi-Chun cheats on A-Wen with Zi-Jie. She feels even more sympathetic to A-Wen. Xiao-Hua later realizes that Zi-Jie never gives his heart to anyone, because he could die at any second. After Zi-jie confesses to Xiao-Hua his love for her, Xiao-Hua’s ex-boyfriend Shao-Ping unexpectedly reappears and stirs up her peace. When Xiao-Hua finally admits her feeling for Zi-Jie, Zi-Jie is ill. Winter is coming to end, will there be a happy ending at the end?