Phineas and Ferb the Movie: Across the 2nd Dimension

In "Phineas and Ferb: Across the 2nd Dimension," the boys finally discover that their beloved pet platypus Perry is in fact a secret agent who battles the forces of evil daily. They join him on an adventure that blasts them to another dimension where a truly evil Dr. Doofenshmirtz has taken over an alternate Tri-state Area. When they uncover his plot to travel back to their dimension to take over their Tri-state Area, the gang, as well as their alter-egos, must band together to stop him.