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The movie was showed on television on Disney Channel on 8/6 and 8/5 2011. In the movie, Phineas and Ferb meet Dr. Doofenshmirtz and unknowingly help him to go into another dimension. In the new dimension, they meet Dr. D's counterpart, who attacks them. Unwantingly, Perry reveals his secret identity as Agent P, causing Phineas to express feelings of hurt. They find thier inter-dimensional counterparts and tell them all about summer through music. Meanwhile, Candace and Stacy are talking about "the mysterious force" that keeps her mom from seeing the wild inventions her brothers have made. Phineas and Ferb open a portal to thier dimension, which Candace and Stacy mistake to be "the mysterious force". Candace goes into the portal, making Stacy believe that "the mysterious force" is real and swallowed Candace. In the parallel dimension, Phineas, Ferb, Candace, Dr. Doofenshmirtz, Perry, and their counterparts have an amazing adventure through muliple universes, including a world filled with floating giant baby heads, a universe with strange creatures, and an alien's bathtub! Eventually, they open a portal to thier own dimension, where Dr. Doofenshmirtz's inter-dimensional twin takes over the Tri-State Area, leading them to discover Agent P's lair. Their past inventions materialize as the computer tells them to get rid of the robots using the boy's inventions. Eventually, Dr. D's eviller twin corners Phineas and Perry, but Dr. Doofenshmirtz appers with Choo-Choo, his old toy. This makes him realize his crimes are useless, and pushes the self-destruct button for all the robots. Just as all the robots blow up, Candace, who had the idea of making "the mysterious force" eliminate the 'bots, leads Linda out of the theater. After seeing no robots, Candace jumps with joy, thinking that she saved the world. Doofenshmirtz's counterpart goes back to his own dimension, and is promptly arrested.