Ai studied abroad until, but after being expelled for quarrelling, his father forces him to return to Thailand where he attends classes at the university where he teaches. There, Ai meets Chen Nhai, his new Harley Davidson-riding classmate who has an obsession with a yellow duck keychain. Ai falls in love at first sight and a whirlwind romance ensues.

About a year after Ai and Chen Nhai start dating, Chen Nhai feels that Ai has changed. Ai starts acting suspiciously which leads to a dispute between the two. Chen Nhai starts to worry about the future of their relationship, so he searches for Ai to appease him.