An ardent youth Yip Ka-ka, whose adoptive mother Bao Choi-yi was her birth mother Yip Heung-heung's best friend, heads her schoolmates to demonstrate against the demolition of the extraordinary school library. In spite of failure, her optimistic personality causes her to shift focus on the preservation of the valuable books together with her geek-looking teacher Chan Ka-keung. Due to their extreme personalities, they argue a lot and seem like to be quarrelsome lovers through the sifting process of less valuable books. Unexpectedly, Ka-ka discovers her birth mother Heung-heung's diary and the truth of her birth parents' love story...