Phineas and Ferb must set out to go across the galaxy to rescue Candace, who has been abducted by aliens and has found utopia in a far-off planet, free of pesky little brothers. The film will chronologically take place before the final episode of the series.
Candace is singing about how she is going to have a perfect day until her younger brothers, Phineas and Ferb, once again create a giant mechanism for their own amusement, infuriating her. Across town, Perry the Platypus is battling Dr. Doofenshmirtz who created an -inator that turns things into lint. The -inator goes off and hits Phineas and Ferb's invention, causing it to crumble just in time for Candace's mother, Linda, to return and not see it. Candace berates her brothers for how things always seem to work out for them, but never for her and sulks. Phineas and Ferb, believing that Candace has never had any fun all summer, decide to make a gift for her.
Vanessa finds Candace sulking and analyzes her problem; telling her that her frustration is not about Phineas and Ferb, but rather that she herself feels insignificant. Before Candace can complete this realization, a space pod appears and sucks her and Vanessa up in it and blasts off. Phineas and Ferb witness the event and analyze its license plate from a planet called Feebla-Oot in the Vroblok Cluster. Perry also witnesses the event and is told by Major Monogram that he must rescue Candace, but without being seen. The kids get together to build a portal that will take them to Feebla-Oot, but instead sends them to Doofenshmirtz's lab; he too learned of Vanessa's capture and tried to do the same thing. They realize that Feebla-Oot has a force field around it and that they will need to travel via spaceship.
Candace and Vanessa explore the space ship they have been taken too and locate the escape pods. While Vanessa escapes, Candace is captured, however both end up on Feebla-Oot anyway. Candace is taken to the leader, the oddly named Super Super Big Doctor who sympathizes with Candace's plight. She too has two younger brothers that she was tired of and decided to come to Feebla-Oot to escape them. Big Doctor informs Candace that she contains "Remarkalonium" which is important for their people and the two spend the day together having fun. The gang arrive on Feebla-Oot, thanks to Perry who has secretly been helping them, and they manage to locate the alien city.
Upon arriving, Phineas and Ferb try to patch things up with Candace by giving her a gift they made, but she rebuffs them and Big Doctor has them taken away. They end up transported onto a truck along with another alien species called the Cowards. They are freed by Perry and escape to the Cowards' hidden city. Candace discovers Big Doctor's real plan for her; her "Remarkalonium" is actually just Carbon dioxide which is needed to feed a spore plant, dubbed Mama, to keep her people in line. Candace accidentally reveals that Earth is full of people who exhale Carbon dioxide and Big Doctor announces her intent to conquer Earth.
Phines and Ferb lead an assault on the alien city and then proceed to follow Big Doctor and Candace onto their ship. Doofenshmirtz stays behind when he learns that Vanessa is still on the planet. Reuniting with Perry they learn that Vanessa has tamed a winged creature and plot to return home. Phineas, Ferb and their friends escape the ship and land on Earth just as Big Doctor unleashes Mama on the populace allowing it grow. While Isabella, Buford and Baljeet fight the aliens, Phineas and Ferb free Candace who cries in shame over how she treated her brothers. They reveal that her gift is a coffee mug that projects images of their past adventures. While Candace may not be special to the world, she is special to them. They band together and fight the aliens.
Mama unleashes her spores which take over the populace and they capture the gang. Candace uses what Vanessa had told her earlier and manages to get through to Big Doctor who realizes that she does not need to take over another planet. However, Mama grows considerably and devours her and then chases the kids through the city. Doofenshmirtz and Vanessa arrive on the winged creature, having used Doofenshmirtz's Chicken-replace-inator to transport themselves to Earth. Candace uses the -inator on Mama and sends her back to Feebla-Oot where is shrinks back down and Big Doctor is captured by the Cowards. Candace has the chance to tattle on her brothers when Linda drives by, but she instead tells her to go get pizza for them.
As Candace, Phineas and Ferb celebrate their victory with their friends, their father Lawrence, discovers their portal in the backyard and enters it; ending up in Dr. Doofenshmirtz's lab which was still on fire from the rocket's fire. He returns and accidentally destroys the portal with Linda, once again what happened, wondering he has been doing.
- Vincent Martella as Phineas
- Ashley Tisdale as Candace
- David Errigo Jr. as Ferb
- Dan Povenmire as Doofenshmirtz, Additional Voices
- Alyson Stoner as Isabella
- Maulik Pancholy as Baljeet, Additional Voices
- Bobby Gaylor as Buford
- Dee Bradley Baker as Perry, Mama, Additional Voices
- Olivia Olson as Vanessa
- Ali Wong as Super Super Big Doctor
- Wayne Brady as Stapler-Fist, Additional Voices
- Thomas Middleditch as Garnoz
- Diedrich Bader as Borthos
- Thomas Sanders as Throat-Lobster
- Caroline Rhea as Mom
- Richard O'Brien as Dad
- Mitchel Musso as Jeremy
- Kelly Hu as Stacy
- Tyler Alexander Mann as Carl
- Jeff "Swampy" Marsh as Major Monogram, Additional Voices
- Brock Powell as Braxington-ton, Vlorkel, Shoe Monkey, Additional Voices
- Bill Farmer as Hermellivue, Additional Voices
- Bob Bowen as Toilet Flower, Additional Voices
- Sarah Hudson as Ernox
- John Viener as Norm
- Corey Burton as Farmer, Additional Voices
- Jennifer Hughes as Farmer's Wife, Additional Voices
- John O'Hurley as Roger Doofenshmirtz
- Emo Phillips as Meeks Servant
- Al Yankovic as Shirt Cannon Guy
- Tiffany Haddish as "The Sound Someone Makes When They Explode From The Waist Up"
- Additional Voices: Laura Dickinson, Aaron Daniel Jacob
Originally announced in 2011, the movie was originally set to be released on July 26, 2013, but it was delayed to a 2014 date to be determined later. However, Deadline Hollywood reported on August 16, 2013 that the movie had been removed from Disney's release schedule. On the same day, Jeff "Swampy" Marsh stated on Twitter that the film was in development hell.
During the winter press tour of the Television Critics Association on January 10, 2011, Gary Marsh, chief creative officer of Disney Channels worldwide, announced that Walt Disney Studios was in the early stages of developing a Phineas and Ferb feature film. It was being developed by Sean Bailey, Disney's president of motion picture production.
On October 27, 2011, it was announced that Michael Arndt, the Academy-Award nominated writer of Little Miss Sunshine and Toy Story 3 (and who was later announced as the screenwriter of Star Wars: The Force Awakens), was revising Povenmire and Marsh's original draft of the script and that David Hoberman and Todd Lieberman of Mandeville Films, who had recently produced The Muppets for Disney, had signed on as producers. Todd Lieberman said that "It will be like Roger Rabbit, where we'd keep those characters and put them in the real world."
On April 11, 2019, after years of silence, Disney announced that a Phineas and Ferb feature film will be made by Disney Television Animation as an exclusive for the Disney+ service and will feature most of the original voice cast reprising their roles. Writer Jim Bernstein confirmed that the new movie is unrelated to the previous production which was originally about the animated characters ending up in a live-action world.
- "Such a Beautiful Day"
- "The Universe is Against Me"
- "Space Adventure"
- "Chop Away at My Heart"
- "Unsung Hero"
- "Meet Our Leader"
- "Girls Day Out"
- "This Is Our Battle Song"
- "Us Against the Universe"
- "We're Back"
- "Step into the Great Unknown" (deleted song)
- This is the second Phineas and Ferb film and the second film overall in the Phineas and Ferb/Milo Murphy's Law universe (also known as the "Dwampyverse").
- This is the first Disney+ original movie to be animated.
- This is also the first Disney+ Original Movie without the Disney logo.
- The songs for the film will be from Kate Micucci and Smallfoot director/co-writer Karey Kirkpatrick as confirmed from the new still. 
- Dan Povenmire confirms this will not take place after "Last Day of Summer". It will take place prior to the events as he confirms it will be treated as a lost episode.
- Cite error: Invalid
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- "Dan Povenmire Post". Twitter (April 13, 2019).
- Phineas and Ferb movie release date, Animation Magazine
- http://www.deadline.com/2013/08/the-avengers-sequel-gets-a-title/ Phineas And Ferb Off Disney’s Release Schedule
- "Disney+ launch date announced". www.thewaltdisneycompany.com. Retrieved on April 11, 2019.
- Producers Compare 'Phineas & Ferb' Film to 'Roger Rabbit' Hybrid Mix
- "Jim Bernstein Post". Twitter (April 11, 2019).
- Phineas and Ferb the Movie: Candace Against the Universe on Wikipedia
- Phineas and Ferb Wiki: Candace Against the Universe