Yeh Xin's (Tia Lee) life seems to be perfect: young, beautiful, top student specializing in criminal psychology, loving parents, and a charming boyfriend Lin Miao (Ray Chang) who is a forensics specialist. One day, Xin's father flies to the USA for a medical seminar. Then on one rainy night, her dog digs up a human bone in her backyard. Next, she receives a letter in the mail warning that her seemingly perfect life is about to collapse.
While the investigation going, Xin accidentally finds hundreds of letters written by a girl named Bugzy, in her boyfriend's study room. Suspecting being cheated and being jealous; Xin begins to read the letters. She then discovers that other than Zhihuan, two other girls are also accidentally died because of Xin's boyfriend. Was it all murder? Who will survive and what will be left at the end?
''When Geek Meets Serial Killer'' director Remus Kam adapts a 2007 novel by popular online writer Ye Congling into the suspense thriller ''The Perfect Girl''. ''When Geek Meets Serial Killer's lead actor Ray Chang stars again, this time opposite Taiwan television actress Tia Lee (Fall in Love with Me) as the heroine who finds out she's not so perfect after all.