Return Policy Phineas and Ferb : Season 4 Episode 31

Annoyed at waiting in really long lines at the return counter, Doofenshmirtz invents a "Back-to-the-Store-inator" to send things back to the store where they came. Meanwhile, Phineas and Ferb stage an extreme batting challenge their friends take place in, and Candace's obsession to bust coincides with her and Jeremy's visit to the Extreme Water Park.