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.