The film opens in the present day, where Lin Zhen Xin (Joe Chen) is an ordinary office worker who gets ridiculed by her subordinates. Dejected, she listens to a cassette recording of an old Andy Lau song. This brings her back to her high school days, where she was an ordinary high school girl. She has a crush on Ou Yang Fei Fan (Dino Li), the school’s most popular male student. One day, Zhen Xin (Vivian Sung) receives a chain letter, warning her of impending doom if she does not pass the message on. Naively, she passes it on to Xu Tai Yu (Darren Wang), the school’s notorious gangster boss, her math teacher and Tao Min Min (Dewi Chien), the school’s most popular girl. While Tai Yu was reading the letter, he got injured in an car accident. After weeding out the letter’s sender, the angry Tai Yu made Zhen Xin his ‘friend’ and forced her to run errands for him in exchange for leaving Fei Fan alone, thus making her his errand-girl. By chance, Zhen Xin accidentally overhears a conversation between Min Min and Fei Fan and discovers that they are in a secret relationship. Dejected, she creates an alliance with Tai Yu, who likes Tao Min Min, to break the couple up. Throughout the course of events, Zhen Xin and Tai Yu began to understand each other better, and their friendship evolves as they began to learn a thing or two about true love. However, Tai Yu gets into trouble with the school authorities and to avoid anymore problems, his parents decide to send him overseas, leaving Zhen Xin with no way to contact him in an era without social media. 18 years later, Zhen Xin leaves her unhappy job and relationship upon having rediscovered herself. She is still unable to book a ticket to an Andy Lau concert that is set to take place in Taipei, where our two main characters, Zhen Xin and Tai Yu (Jerry Yan), will be reunited.
林真心（宋芸樺 飾），一個平凡的高中女生，喜歡上全校最受歡迎的男神歐陽非凡（李玉璽 飾）。某天在學校時發現收到了一封幸運信，卻也因此意外的認識徐太宇（王大陸 飾）。而因為一次去清掃泳池時，不小心聽到心上人歐陽非凡和校花陶敏敏（簡廷芮 飾）的秘密；在喜歡陶敏敏的流氓學生徐太宇的脅迫下，兩人組成「失戀陣線聯盟」，誓言拆散這對戀人，幫助彼此倒追心上人。