每個人都有一個綽號，差別在於好不好聽！

碧昂卡是個不修邊幅，一般般的高中女孩，雖然身旁的姊妹淘個個都長得比她正，但她一點也不在意。直到她從別人口中聽見自己被取了「恐龍妹」的綽號，使她開始心有不甘。為了不再讓自己成為姊妹淘的影子，碧昂卡決心自己站出來，要好好改造自己，徹底甩掉這個難聽的綽號，還要展現自己獨特的美麗，令大家跌破眼鏡。

Bianca is a content high school senior whose world is shattered when she learns the student body knows her as 'The DUFF' (Designated Ugly Fat Friend) to her prettier, more popular friends. Now, despite the words of caution from her favorite teacher, she puts aside the potential distraction of her crush, Toby, and enlists Wesley, a slick but charming jock, to help reinvent herself. To save her senior year from turning into a total disaster, Bianca must find the confidence to overthrow the school's ruthless label maker Madison and remind everyone that no matter what people look or act like, we are all someone's DUFF.