"Birthday Adventure" is a children's film that tells the story of Lan (or Wu Lan), a "left-behind child" in the countryside, looking for her mother in the city.

Wu Lan is a seven-year-old,girl: she's courageous, optimistic, strong, and independent. She misses her mother terribly, who has gone into the city to find work and has not returned for over a year. Leaving a note for her grandmother, she takes her pet lamb Dumpling and sneaks away to find her mother. Mr. Tang, Lan's teacher, catches up with Lan. They found Lan's brother, Kong (or Wu Kong), at Shaolin Temple, where he practices as a Shaolin disciple. Mr. Tang decides to take the siblings to the city to find their mother. The Pattra-leaf Buddhist Scriptures were first stolen by the thief Mingliang and then taken by Lan by mistake. Mingliang has secretly followed them in order to get the Scriptures back. These four people with different personalities set out on a journey to find the mother, and a series of thrilling and hilarious adventures take place. The film is both witty and touching, as the journey to find the mother is also the journey of personal development and discovery for each of the travelers. Optimisitc and brave stories are even more important now, in the troubled times in which we live.