Phineas and Ferb the Movie: Candace Against the Universe, on Disney+
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Caution: spoilers.

This was released online in 2020, five years after the TV series Phineas and Ferb ended. I didn't see it until 2025, because it took me that long to catch up on the series. The movie is apparently set sometime during (but before the end of) the fourth season of the show. I'm not really sure how that works, since at the end of the movie, it doesn't seem like Candace will continue trying to bust her brothers, as she did throughout the series, but by the end of the series, she is still trying to bust them. But whatever. It's a really fun movie, anyway.

It begins with Candace riding her bicycle and singing about what a beautiful day it is, and trying to suppress her desire to bust Phineas and Ferb. When she gets home, she sees her brothers and their friends are up to one of their usual activities, and tries to bust them for it. But this time, when she fails, she is more dejected than ever, and informs her brothers that she's been having a lousy summer. They're sorry about that, as they had assumed she was enjoying the summer as much as they were. So they decide to make her a present. Meanwhile, Candace sites outside crying, when Vanessa happens by, and stops to console her. Then a spaceship appears, which Candace assumes was created by her brothers. Actually, it was an alien craft, which abducts her and Vanessa and transports them to an alien planet called Feebla-Oot. Perry sees the abduction, and Major Monogram instructs him to rescue her without revealing that he's a secret agent.

Phineas and Ferb also witness the abduction, and are determined to rescue Candace, themselves. So they and their friends build a portal that's meant to take them to Feebla-Oot, but due to an ion barrier around the planet, the portal gets redirected to another portal, which Dr. Doofenshmirtz had built to rescue Vanessa (who had posted her predicament on social media). So everyone decides to use Doof's spaceship to go to Feebla-Oot, and Perry sneaks aboard. Meanwhile, the ship carrying Candace and Vanessa docks with a mothership. Vanessa uses an escape pod, hoping to return to Earth, but it crash lands on Feebla-Oot. Candace is captured by the aliens, who take her to their leader, who is named Super Super Big Doctor (voiced by Ali Wong). It turns out that Candace is "the Chosen One", as she produces a substance the aliens require, called Remarkalonium. So they all treat her as special, which makes her feel better about herself. She and Super Super Big Doctor also do a lot of bonding, becoming almost like sisters.

Doof's ship crash lands on Feebla-Oot, and he and the kids have to search for Candace and Vanessa. Doof and Isabella argue about who should be in charge of the rescue mission. Doof sings a song about "adulting", which no one else in the movie thinks is a verb, but I do, so whatever. When they eventually find Candace, she tells them she's happy here, and doesn't want them around. Super Super Big Doctor says she'll "take care of them", which Candace assumes means she'll treat them as guests, but in actuality she sends them to a dungeon. But they never arrive there, as the transport is secretly stopped by Perry. Doof and the kids meet some aliens who were also being sent to the dungeon, who take the group to their hidden city, and tell them how Super Super Big Doctor became their leader. Which I guess I don't want to spoil. But eventually, the truth is revealed to Candace, and something she says makes Super Super Big Doctor decide to invade Earth. So the kids will have to try to stop them. Meanwhile, Doof finds Vanessa (or rather, she finds him and Perry). But they're all stuck on Feebla-Oot, at least for the time being. They do eventually get back to Earth, though. And of course the aliens are ultimately defeated.

Well, I may have said too much, but believe me, I've left out a ton of details. The whole movie is funny, and exciting, and has some fun songs, and is rather touching in how it deals with Candace's eventual reconciliation with her brothers. As always, there are lots of clever touches throughout the story. And while it may not be one of my favorite Phineas & Ferb stories ever, it's still pretty dang great in every way.