Lu Yunfei returns to Shanghai from abroad and embarks on his career in the advertising industry. He has always been about why his girlfriend Su Fei broke up with him and has been unable to contact her despite continuous phone calls and SMSes. Su Fei's mobile number expires due to inactivity and the number is now used by Mu Beibei. The touching SMSes impress her and she goes online to a mobile virtual community to chat with the sender, nicknamed 'Edge of the Iceberg'. They soon become fast friends.
Yunfei and his team arrive in Yunnan to do a cellphone commercial and select Beibei as their model by chance. When Beibei wins a writing competition based on her encounter with 'Iceberg Edge', she decides to go to Shanghai to fulfill her dream. Beibei runs into Yunfei there but their already sour relationship worsens with further misunderstandings. Beibei also meets Lin Lizhong, who helps her out many times.
Beibei and Yunfei begin to admire and respect each other after some time while Lizhong also falls for Beibei. Although Yunfei begins to feel stirrings of love for Beibei, he withholds his feeling. It is only when Beibei has accepted Lizhong that Yunfei and Beibei accidentally discover that they are actually best friends in the mobile virtual community. Beibei and Yunfei nevertheless part ways after some time. While in Beijing one day, Beibei realizes that Yunfei has sent out search notices for her via the mobile network. With help from virtual friends online, Yunfei finally tracks down Beibei. She agrees to grant him another chance if he is able to fulfill one condition: Yunfei must send out a chain SMS and the message must eventually reach Beibei within a week… (source: dramawiki)