Phineas and Ferb Season 1 Episode 40
The Monster of Phineas-n-Ferbenstein
The boys learn about one of Ferb's Victorian ancestors, who helped a scientist create a monster. Meanwhile, Doofenshmirtz recalls the story of his great-great-grandfather Dr. Jekyll Doofenshmirtz.
Guest Stars
Malcolm McDowell
Grandpa Reg (voice)
Jennifer Grey
Additional Voices (voice)
Jane Carr
Grandma Winifred Fletcher (voice)
Jeff Bennett
Additional Voices (voice)
Candi Milo
Additional Voices (voice)