Episode 1: Rollercoaster
Season 1, Episode 1a: Phineas & Ferb make a rollercoaster; Dr. Doofenshmirtz covers the eastern seaboard in tinfoil.
Season 1, Episode 1a: Phineas & Ferb make a rollercoaster; Dr. Doofenshmirtz covers the eastern seaboard in tinfoil.