We have come to the last day of summer and stepbrothers Phineas (Vincent Martella) and Ferb (Thomas Brodie-Sangster) want to end it with a bang. Meanwhile, Dr. Doofenshmirtz (Dan Povenmire) has come up with a plan to take over the world and Perry the Platapus is helpless to stop him.
Based on the popular children's television show of the same name, this film brings the stepbrothers' adventures to the big screen.