S01E40: 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.
Previous Episode 
Season 1
Rollercoaster
S1E1 / 17 Aug 2007
Lawn Gnome Beach Party of Terror
S1E2 / 28 Sep 2007
Flop Starz
S1E3 / 01 Feb 2008
The Fast and the Phineas
S1E4 / 02 Feb 2008
Lights, Candace, Action!
S1E5 / 03 Feb 2008
Raging Bully
S1E6 / 04 Feb 2008
Candace Loses Her Head
S1E7 / 05 Feb 2008
I, Brobot
S1E8 / 06 Feb 2008
Run Away Runway
S1E9 / 07 Feb 2008
The Magnificent Few
S1E10 / 08 Feb 2008
S'Winter
S1E11 / 09 Feb 2008
Jerk De Soleil
S1E12 / 10 Feb 2008
Are You My Mummy?
S1E13 / 15 Feb 2008
Ready For The Bettys
S1E14 / 16 Feb 2008
I Scream, You Scream
S1E15 / 17 Feb 2008
Toy to the World
S1E16 / 22 Feb 2008
Get That Bigfoot Outa My Face!
S1E17 / 23 Feb 2008
It's a Mud, Mud, Mud, Mud World
S1E18 / 24 Feb 2008
Mom's Birthday
S1E19 / 29 Feb 2008
Journey to the Center of Candace
S1E20 / 29 Feb 2008
It's About Time!
S1E21 / 01 Mar 2008
Dude, We're Getting the Band Back Together
S1E22 / 08 Mar 2008
Tree to Get Ready
S1E23 / 22 Mar 2008
The Ballad of Badbeard
S1E24 / 12 Apr 2008
Greece Lightning
S1E25 / 19 Apr 2008
Leave the Busting to Us
S1E26 / 19 Apr 2008
Crack That Whip
S1E27 / 24 May 2008
The Best Lazy Day Ever
S1E28 / 24 May 2008
Boyfriend From 27,000 B.C.
S1E29 / 07 Jun 2008
Voyage to the Bottom of Buford
S1E30 / 07 Jun 2008
A Hard Day's Knight
S1E31 / 14 Jun 2008
Traffic Cam Caper
S1E32 / 12 Jul 2008
Bowl-R-Rama Drama
S1E33 / 12 Jul 2008
Got Game?
S1E34 / 02 Aug 2008
Comet Kermilian
S1E35 / 02 Aug 2008
Put That Putter Away
S1E36 / 10 Aug 2008
Does This Duckbill Make Me Look Fat?
S1E37 / 10 Aug 2008
The Flying Fishmonger
S1E38 / 12 Sep 2008
One Good Scare Ought to Do It!
S1E39 / 03 Oct 2008
The Monster of Phineas-n-Ferbenstein
S1E40 / 17 Oct 2008
Oil on Candace
S1E41 / 17 Oct 2008
Out of Toon
S1E42 / 07 Nov 2008
Hail Doofania!
S1E43 / 07 Nov 2008
Out to Launch
S1E44 / 05 Dec 2008
Phineas and Ferb Get Busted
S1E45 / 16 Feb 2009
Unfair Science Fair
S1E46 / 17 Feb 2009
Unfair Science Fair Redux (Another Story)
S1E47 / 18 Feb 2009
Season 2
The Lake Nose Monster
S2E1 / 19 Feb 2009
Interview with a Platypus
S2E2 / 20 Feb 2009
Tip of the Day
S2E3 / 21 Feb 2009
Attack of the 50 Foot Sister
S2E4 / 21 Feb 2009
Backyard Aquarium
S2E5 / 21 Feb 2009
Day of the Living Gelatin!
S2E6 / 28 Feb 2009
Elementary, My Dear Stacy
S2E7 / 28 Feb 2009
Don't Even Blink
S2E8 / 04 Apr 2009
Chez Platypus
S2E9 / 04 Apr 2009
Perry Lays an Egg
S2E10 / 11 Apr 2009
Gaming the System
S2E11 / 11 Apr 2009
The Chronicles of Meap
S2E12 / 18 Apr 2009
Thaddeus and Thor
S2E13 / 15 Jun 2009
De Plane! De Plane!
S2E14 / 15 Jun 2009
Let's Take a Quiz
S2E15 / 22 Jun 2009
At the Car Wash
S2E16 / 22 Jun 2009
Oh, There You Are, Perry!
S2E17 / 11 Jul 2009
Swiss Family Phineas
S2E18 / 11 Jul 2009
Hide and Seek
S2E19 / 18 Jul 2009
That Sinking Feeling
S2E20 / 18 Jul 2009
The Baljeatles
S2E21 / 25 Jul 2009
Vanessassary Roughness
S2E22 / 25 Jul 2009
No More Bunny Business
S2E23 / 01 Aug 2009
Spa Day
S2E24 / 01 Aug 2009
Phineas and Ferb's Quantum Boogaloo
S2E25 / 25 Sep 2009
Phineas and Ferb's Musical Cliptastic Countdown
S2E26 / 16 Oct 2009
Bubble Boys
S2E27 / 17 Oct 2009
Isabella and the Temple of Sap
S2E28 / 17 Oct 2009
Cheer Up, Candace
S2E29 / 24 Oct 2009
Fireside Girl Jamboree
S2E30 / 24 Oct 2009
The Bully Code
S2E31 / 31 Oct 2009
Finding Mary McGuffin
S2E32 / 31 Oct 2009
Picture This
S2E33 / 07 Nov 2009
Nerdy Dancin'
S2E34 / 07 Nov 2009
What Do It Do
S2E35 / 14 Nov 2009
Atlantis
S2E36 / 14 Nov 2009
Phineas and Ferb Christmas Vacation
S2E37 / 06 Dec 2009
Just Passing Through
S2E38 / 06 Feb 2010
Candace's Big Day
S2E39 / 06 Feb 2010
I Was a Middle Aged Robot
S2E40 / 13 Feb 2010
Suddenly Suzy
S2E41 / 13 Feb 2010
Undercover Carl
S2E42 / 13 Feb 2010
Hip Hip Parade
S2E43 / 13 Feb 2010
Invasion of the Ferb Snatchers
S2E44 / 20 Feb 2010
Ain't No Kiddie Ride
S2E45 / 20 Feb 2010
Not Phineas and Ferb
S2E46 / 27 Feb 2010
Phineas and Ferb-Busters
S2E47 / 27 Feb 2010
The Lizard Whisperer
S2E48 / 06 Mar 2010
Robot Rodeo
S2E49 / 06 Mar 2010
The Beak
S2E50 / 08 Mar 2010
She's the Mayor
S2E51 / 14 Jun 2010
The Lemonade Stand
S2E52 / 14 Jun 2010
Phineas and Ferb Hawaiian Vacation (1)
S2E53 / 09 Jul 2010
Phineas and Ferb Hawaiian Vacation (2)
S2E54 / 09 Jul 2010
Phineas and Ferb: Summer Belongs to You!
S2E55 / 02 Aug 2010
Nerds of a Feather
S2E56 / 16 Aug 2010
Wizard of Odd
S2E57 / 24 Sep 2010
We Call it Maze
S2E58 / 01 Oct 2010
Ladies and Gentlemen, Meet Max Modem!
S2E59 / 01 Oct 2010
The Secret of Success
S2E60 / 08 Oct 2010
The Doof Side of the Moon
S2E61 / 08 Oct 2010
Split Personality
S2E62 / 29 Oct 2010
Brain Drain
S2E63 / 29 Oct 2010
Rollercoaster: The Musical!
S2E64 / 28 Jan 2011
Make Play
S2E65 / 11 Feb 2011
Candace Gets Busted
S2E66 / 11 Feb 2011
Season 3
The Great Indoors
S3E1 / 04 Mar 2011
Canderemy
S3E2 / 04 Mar 2011
Run, Candace, Run
S3E3 / 11 Mar 2011
Last Train to Bustville
S3E4 / 11 Mar 2011
Phineas' Birthday Clip-o-Rama!
S3E5 / 01 Apr 2011
The Belly of the Beast
S3E6 / 29 Apr 2011
Moon Farm
S3E7 / 29 Apr 2011
Ask a Foolish Question
S3E8 / 13 May 2011
Misperceived Monotreme
S3E9 / 13 May 2011
Candace Disconnected
S3E10 / 18 Jun 2011
Magic Carpet Ride
S3E11 / 18 Jun 2011
Bad Hair Day
S3E12 / 24 Jun 2011
Meatloaf Surprise
S3E13 / 24 Jun 2011
Phineas and Ferb Interrupted
S3E14 / 15 Jul 2011
A Real Boy
S3E15 / 15 Jul 2011
Mommy Can You Hear Me?
S3E16 / 29 Jul 2011
Road Trip
S3E17 / 29 Jul 2011
Tour de Ferb
S3E18 / 12 Aug 2011
Skiddley Whiffers
S3E19 / 26 Aug 2011
My Fair Goalie
S3E20 / 09 Sep 2011
Bullseye!
S3E21 / 30 Sep 2011
That's the Spirit
S3E22 / 07 Oct 2011
The Curse of Candace
S3E23 / 07 Oct 2011
Escape From Phineas Tower
S3E24 / 21 Oct 2011
Lotsa Latkes
S3E25 / 18 Nov 2011
Ferb Latin
S3E26 / 25 Nov 2011
A Phineas and Ferb Family Christmas
S3E27 / 02 Dec 2011
Tri-Stone Area
S3E28 / 13 Jan 2012
Doof Dynasty
S3E29 / 14 Jan 2012
Excaliferb
S3E30 / 15 Jan 2012
Phineas and Ferb and the Temple of Juatchadoon
S3E31 / 20 Jan 2012
Monster from the Id
S3E32 / 10 Feb 2012
Gi-Ants
S3E33 / 10 Feb 2012
The Remains of the Platypus
S3E34 / 24 Feb 2012
Mom's In The House
S3E35 / 02 Mar 2012
Perry the Actorpus
S3E36 / 03 Mar 2012
Let's Bounce
S3E37 / 16 Mar 2012
Bully Bromance Break Up
S3E38 / 16 Mar 2012
Quietest Day Ever
S3E39 / 30 Mar 2012
The Doonkelberry Imperative
S3E40 / 30 Mar 2012
Meapless in Seattle
S3E41 / 06 Apr 2012
Delivery of Destiny
S3E42 / 27 Apr 2012
Buford Confidential
S3E43 / 27 Apr 2012
The Mom Attractor
S3E44 / 04 May 2012
Cranius Maximus
S3E45 / 04 May 2012
Agent Doof
S3E46 / 11 May 2012
Minor Monogram
S3E47 / 11 May 2012
What A Croc!
S3E48 / 01 Jun 2012
Sleepwalk Surprise
S3E49 / 08 Jun 2012
Sci-Fi Pie Fly
S3E50 / 08 Jun 2012
Sipping with the Enemy
S3E51 / 22 Jun 2012
Tri-State Treasure: Boot of Secrets
S3E52 / 22 Jun 2012
Doofapus
S3E53 / 06 Jul 2012
Norm Unleashed
S3E54 / 20 Jul 2012
Where's Perry (1)
S3E55 / 26 Jul 2012
Where's Perry (2)
S3E56 / 24 Aug 2012
Ferb TV
S3E57 / 07 Sep 2012
When Worlds Collide
S3E58 / 14 Sep 2012
What'd I Miss?
S3E59 / 17 Sep 2012
Road to Danville
S3E60 / 26 Oct 2012
This is Your Backstory
S3E61 / 02 Nov 2012
Blackout
S3E62 / 30 Nov 2012
Season 4
For Your Ice Only
S4E1 / 07 Dec 2012
Happy New Year!
S4E2 / 07 Dec 2012
Fly on the Wall
S4E3 / 11 Jan 2013
Bully Bust
S4E4 / 18 Jan 2013
My Sweet Ride
S4E5 / 01 Feb 2013
Der Kinderlumper
S4E6 / 15 Feb 2013
Sidetracked
S4E7 / 01 Mar 2013
Primal Perry
S4E8 / 02 Mar 2013
Mind Share
S4E9 / 05 Apr 2013
Backyard Hodge Podge
S4E10 / 19 Apr 2013
Bee Day
S4E11 / 26 Apr 2013
Bee Story
S4E12 / 26 Apr 2013
Great Balls of Water
S4E13 / 07 Jun 2013
Where's Pinky?
S4E14 / 14 Jun 2013
Phineas and Ferb's Musical Cliptastic Countdown Hosted by Kelly Osbourne
S4E15 / 28 Jun 2013
Knot My Problem
S4E16 / 05 Jul 2013
Just Desserts
S4E17 / 05 Jul 2013
La Candace-Cabra
S4E18 / 12 Jul 2013
Happy Birthday, Isabella
S4E19 / 12 Jul 2013
Love at First Byte
S4E20 / 02 Aug 2013
One Good Turn
S4E21 / 09 Aug 2013
Phineas and Ferb: Mission Marvel
S4E22 / 16 Aug 2013
Thanks But No Thanks
S4E23 / 13 Sep 2013
Troy Story
S4E24 / 20 Sep 2013
Druselsteinoween
S4E25 / 04 Oct 2013
Terrifying Tri-State Trilogy of Terror
S4E26 / 05 Oct 2013
Face Your Fear
S4E27 / 11 Oct 2013
Cheers for Fears
S4E28 / 01 Nov 2013
Steampunx
S4E29 / 15 Nov 2013
Just Our Luck
S4E30 / 10 Jan 2014
Return Policy
S4E31 / 24 Jan 2014
Live and Let Drive
S4E32 / 01 Mar 2014
Phineas and Ferb Save Summer
S4E33 / 09 Jun 2014
Father's Day
S4E34 / 10 Jun 2014
Imperfect Storm
S4E35 / 11 Jun 2014
The Return of the Rogue Rabbit
S4E36 / 16 Jun 2014
It's No Picnic
S4E37 / 23 Jun 2014
The Klimpaloon Ultimatum
S4E38 / 07 Jul 2014
Operation Crumb Cake
S4E39 / 14 Jul 2014
Mandace
S4E40 / 14 Jul 2014
Phineas and Ferb: Star Wars
S4E41 / 26 Jul 2014
Lost in Danville
S4E42 / 29 Sep 2014
The Inator Method
S4E43 / 29 Sep 2014
Night of the Living Pharmacists
S4E44 / 04 Oct 2014
Tales from the Resistance: Back to the 2nd Dimension
S4E45 / 25 Nov 2014
Doof 101
S4E46 / 27 Nov 2014
Act Your Age
S4E47 / 09 Feb 2015
Last Day of Summer
S4E48 / 12 Jun 2015
Season 5
Summer Block Buster
S5E1 / 26 May 2025
Cloudy with a Chance of Mom
S5E2 / 05 Jun 2025
Submarine Sandwich Submarine
S5E3 / 05 Jun 2025
License to Bust
S5E4 / 05 Jun 2025
Dry Another Day
S5E5 / 14 Jun 2025
Deconstructing Doof
S5E6 / 14 Jun 2025
Tropey McTropeFace
S5E7 / 14 Jun 2025
Biblio-Blast!
S5E8 / 14 Jun 2025
A Chip to the Vet
S5E9 / 21 Jun 2025
More Than an Intern
S5E10 / 21 Jun 2025
The Aurora Perry-Alis
S5E11 / 21 Jun 2025
Lord of the Firesides
S5E12 / 21 Jun 2025
The Candace Suit
S5E13 / 28 Jun 2025
Agent T (for Teen)
S5E14 / 28 Jun 2025
The Haberdasher
S5E15 / 28 Jun 2025
Out of Character
S5E16 / 28 Jun 2025
The Chronicles of Meap Ep. 42 Meap Me in St. Louis
S5E17 / 05 Jul 2025
No Slumber Party
S5E18 / 12 Jul 2025
The Ballad of Bubba Doof
S5E19 / 12 Jul 2025
Attack of the Candace Suit
S5E20 / 19 Jul 2025
Book Flub
S5E21 / 19 Jul 2025
The Bad Old Days
S5E22 / 26 Jul 2025
Mantis Fact!
S5E23 / 26 Jul 2025
The Nightmare-Inator
S5E24 / 02 Aug 2025
Doof in Retrograde
S5E25 / 02 Aug 2025
Bend It Like Doof
S5E26 / 18 Oct 2025
Dooflicated
S5E27 / 18 Oct 2025
Space Adventure
S5E28 / 25 Oct 2025
Droogenfest
S5E29 / 25 Oct 2025
Doofercise
S5E30 / 01 Nov 2025
Croquet Y-8
S5E31 / 01 Nov 2025
Dinner Reservations
S5E32 / 08 Nov 2025
Bread Bowl Hot Tub
S5E33 / 08 Nov 2025
Entrance Exam
S5E34 / 15 Nov 2025
Dungeons & Dating
S5E35 / 15 Nov 2025
Elevator Irritator
S5E36 / 16 Jan 2026
Master of Fate
S5E37 / 16 Jan 2026
VENDPOCALYPSE: THE MUSICAL
S5E38 / 16 Jan 2026
Vincent Martella
Phineas Flynn (voice)
David Errigo Jr.
Ferb Fletcher (voice)
Ashley French
Candace Flynn (voice)
Caroline Rhea
Linda Flynn-Fletcher (voice)
Dee Bradley Baker
Perry the Platypus (voice)
Alyson Stoner
Isabella Garcia-Shapiro (voice)
Dan Povenmire
Heinz Doofenshmirtz (voice)
