Penny Proud is almost 16 years old, but her dad, Oscar, still treats her like a child! First she's told she cannot be one of the dancers in the upcoming hip-hop half-time show. And now, instead of celebrating her sweet 16th birthday with her friends, she has to go on a boring vacation to the tropical Legume Island with her family. But it turns out the island is full of mysteries. The evil Dr. Carver has lured them there in hopes of stealing Oscar's super-secret Instant Everlasting Multiplying Formula. With it, he hopes to take over the world. When Oscar refuses to reveal his secret, Dr. Carver unleashes evil clones of the entire Proud family and Penny and her family must work together to defeat the clones.