劇情：

活潑開朗的女高中生阿丹(陳嘉樺飾)，以維護「幸福」做為自身使命，在學校與好友佩佩、小米組成(大元、方志友飾)「壞女孩」團體，行俠仗義、除暴安良，團結女生力量、抵抗臭男生的惡勢力！

夏天，風靡全亞洲的新生代巨星賈斯汀(賀軍翔飾)，來到小村學校取景拍攝電影。當紅偶像賈斯汀的蒞臨，令小鎮少女為之瘋狂。狀況外的阿丹卻誤闖拍片現場，陰錯陽差之下被指派擔任女主角。向來不被任何事所打倒的阿丹，這次要挑戰的卻是愛情電影！從來沒談過戀愛的阿丹，能夠用怎樣的方式去理解、並且詮釋熱戀中的女孩？高傲的賈斯汀，又要使出什麼絕招，才能與從來沒牽過男生手的阿丹大談戀愛？結合動作、愛情、復古、搞笑、劇中劇…等多項元素，「壞女孩」這次的出擊要顛覆你對台灣電影的全部想像！

Synopsis:

Dan is well versed in martial arts and impulsively stubborn; she's viewed as a distasteful concoction between defiance and justice. She and her girlfriends created a vigilante group called "The Bad Girls" to put an end to all evil. Yet when a film unit arrives at her high-school location for a shoot, a series of coincidences thrusts her straight into limelight. She finds herself playing the female lover of a knight-in-shiny armor, played by the cocky super-idol Justin.