Phineas and Ferb: Mission Marvel

 will be a special Season 4 episode of Phineas and Ferb and serve as an animated crossover between Disney and Marvel that will premiere in the summer of 2013.

Spider-Man, Thor, Iron Man and Hulk arrive in town after their powers are accidentally removed by the evil Dr. Doofenshmirtz. Phineas and Ferb come to the rescue, and they work together to defeat some meddling Marvel villains, including Red Skull, Whiplash and Venom.

Background Information

 * Disney has confirmed that this will be a crossover with Marvel, as is formerly happened with the kids' game Club Penguin.

Continuity

 * Spider-Man- This will be his first appearance. Twice before, the character was imitated in the series canon ("Bowl-R-Ama Drama", "Phineas and Ferb Christmas Vacation!").