Frumpy high-school senior Bianca (Mae Whitman) has a rude awakening when she learns that her classmates secretly know her as the DUFF -- designated ugly fat friend -- to her prettier and more popular pals. Desperate to reinvent herself, Bianca enlists the aid of Wesley (Robbie Amell), a charming jock. In order to save her senior year from becoming a complete disaster, Bianca must find the confidence to overthrow a judgmental student (Bella Thorne) and revolutionize the school's social order.