Phineas And Ferb: Season 2, Episode 8

2 - 8: Don't Even Blink

Fed up with her brother's inventions always disappearing, Candace enlists the help of everyone in the neighborhood to build and watch a big and obvious invention, that they might finally see exactly what happens to everything. Meanwhile, is it mime? No, it's Doofenshmirtz' new Invisibility Ray.