It's been a week since the gang went to the second dimension, and defeated Spider-Venom. And Candace's life is back to normal. But Evil Peter Parker has found the Alien Symbiote, and bonds with it again, but not only that, he found Phineas and Ferb's Cloning machine, and Heinz Doofinsmirtz's Turn Everything Evil-inator, and combines them into one invention, the "Evil Duplicatinator". And he kidnaps Candace, and 2nd Demension Candace and tries to make evil duplicates of them in order to rule his Tri-State area. Now it's up to Danny Phantom, Spider-man, Team Improbable, and Coon and Friends to save the two Candaces, before something "Splits".
The film opens with Danny (David Kaufman) and his friends attending a party at a roller rink for the year's BFL skate night. Here he reunites with his sister, Jasmine Fenton (Colleen 'Shaughnessy). While attempting to skate with Candace, Danny's older adopted brother Peter Parker (Josh Keaton) intervenes, ending with Isabella speaking to him on the loudspeaker and further humiliating him by getting Phineas and Ferb to carry him off the rink. And far on the island of Hawiai, also known as SuperJail, Second Dimension Peter Parker is now imprisoned for terrorist acts, then, the alien symbiote bonds with Second dimension Peter Parker, thus, Spider-Venom was reborn! Peter Parker-2 now reincarnated as Spider- Venom, finds Dr. Doofinsmirtz and suggests joining forces to rule the 2nd dimension Danville, to which Doof agrees. While at a bar with the teenagers of Danville, Peter instantly spots Spider-Venom, runs off to put on his Spider-Man costume with his mask, and starts to battle Spider-Venom, but is easily beaten. Spider-Venom ends up hiding in the Flynn Home, waiting to strike Peter, but he finds Phineas and Ferb's cloning machine, and he decides to steal it, when he sees Dr. Doof, he tells him that he combined "Turn evil-inator" and the cloning machine to make the Evil Duplicatinator.
In the 2nd dimension, the rest of 2nd dimension Danville is cleaning up after the disaster, but Spider-Venom captures 2nd Dimension Candace, and imprisons her in Doof's lair, Spider-Man and Danny Phantom attempt to stop his plan to dominate the 2nd dimension Tri State area, but fails miserably, as they are in a trap, Spider-Venom captures the kids of Danville, Jeremy, Stacy, and Candace, and tells them his plan to duplicate both Candaces 100,000,000,000 times in order to rule 2nd dimension Danville. As the duplication process begins, Peter starts to battle Spider-Venom. Danny and the rest of the gang try to stop the duplication process, but fails. Phineas and Ferb grabs a minature version of the molecular seperator, and splits the duplicator in to 2 parts, the original duplicator and the turn everything evil-inator. The duplication process is finished, but the duplicates aren't evil, and the duplicates join in on the battle, and so does everyone else. Spider-Venom is relentlessly beaten, and 2nd dimension Peter Parker is seperated from the Symbiote as it escapes into the sewers. Later at the Flynn Fletcher home, Peter is wondering what to do with the Candace duplicates, in a similar manner to the Three Stooges Short, "I'll Never Heil again", he disquises a gernade as cue ball, and all the Candaces fight for it, only to have them trapped in the basement
The 2nd dimension Candace is back in her dimension, and the original Candace asks if the duplicates are not going to be seen again. Danny points out that he has locked the Basement, that has a hole that leads to Doof's building. And in the sewers, the symbiote lurks, awaiting to be bonding to 2nd dimension Peter Parker, who is back in Superjail. The movie ends with a clip of Peter smiling before webslinging throughout Danville.
- The Ending is simaliar To the three stooges short, "I'll Never Heil again."
- This will be the only episode to be part of a 3-part Story arc from the Second Demension series.
- This will be the last time that Al Gore has an urge to destroy ManBearPig