Mia Thermopolis is about to discover the truth about her heritage. The secrets that have been kept from her ever since she was born are about to unfold in view of the entire world. The day her father arrived is a day she will never forget. While dining with her father, Mia is told that her father is indeed the Prince of Genovia. Mia has always kept a diary and now more than ever she writes her feelings and thoughts. There are so many issues that she is dealing with: the fact that her father is a Prince, her mother is dating her Algebra teacher, her best friend has disowned her.
She tries to keep her acquired “royalty” a secret but someone has informed the press. She must now face her peers and learn how to be a princess. The boy she has always had a crush on now pays her attention and Mia does not realize until it is too late of his intentions. With help from her best friends’ brother and close friends, Mia rises to the top with a new confidence.