Act I[]
(Scene starts at the Garcia-Shapiro house, where Isabella is eating breakfast with her mom, suddenly a doorbell rings)
Vivian: I'll go get it. (opens the door, Linda & Lawrence are there) Why, hello there, Linda & Lawrence!
Linda: Hi, Vivian! We were just planning to make a cake for the wedding.
Vivian: What wedding?
Linda: My son Phineas wants to marry your daughter, Isabella.
Vivian: Oh, how-Wait. Isn't Phineas a little young to marry my daughter?
Lawrence: Yes, yes he is.
(Scene cuts to the Flynn-Fletcher house, where Phineas is in his bedroom staring at a picture of Isabella & Phineas when they were younger)
Phineas: Oh, how I wish I was with this girl forever.
(Candace enters his bedroom)
Candace: Good morning, Phineas!
Phineas: Morning, Candace!
Candace: Say, what are you staring at this picture for?
Phineas: Don't you see, Candace? I'm gonna marry Isabella!
Candace: Aw, how sweet! Can I write a postcard for you?
Phineas: No thanks.
Candace: Can I buy her a new car for your honeymoon?
Phineas: Already done.
Candace: Is there anything that I get to do?
Ferb: You could tell me what engagement ring I have to buy for him & Isabella.
Candace: OK then. We're taking my car. (stops walking, starts to weep) My little brother's getting married! (stops weeping, she & Ferb go outside, and get into Candace's car.)
Phineas: Hey, where's Perry?
(Perry enters his hideout)
Major Monogram: Good morning, Agent P. Brendan is currently planning to ruin someone's wedding.
Carl: And I'm one of the secret guests!
Major Monogram: Quiet, Carl! Anyways, you better head down to Brendan's Evil Inc. pronto!
Act II[]
(Scene cuts to the Flynn-Fletcher backyard, Isabella comes into the backyard)
Isabella: Hi, Phineas! Whatcha-(gets blindfolded) HEY!!
Phineas: I don't want to ruin our wedding surprise! You'll have to wait just a little longer!
Isabella: Oh, OK. But that doesn't mean you have to blindfold me!
Phineas: Sorry, I don't want to spoil our surprise for you. We're working on it. (removes blindfold) In the meantime though, why not just let ourselves lie down under a tree and remember all of our times together.
Isabella: OK.
(Cue flashback. We first see Isabella looking at Phineas during "Rollercoaster")
Isabella: I can't forget the first time I saw you and I fell in love.
(Then we see Phineas & Isabella hugging in "Summer Belongs to You!")
Phineas: And that hug.
(Then comes Phineas & Isabella's first kiss from "Phineas & Ferb Across the 2nd Dimension")
Isabella: Who could forget that first kiss, too?
Phineas: All of my friends.
Isabella: Right.
(Then we see Isabella making a confession to Phineas during "Night of the Living Pharmacists". Cue record scratch)
Isabella: Wait a second! We're not supposed to remember that!
Phineas: Exactly! (Flashback ends) Well, that was romantic!
Isabella: (dreamily) It sure was!
Phineas: Hey, can you please meet me at Slushy Burger's at 7 PM?
Isabella: OK! See ya!
Phineas: Bye now!
♪ Brendan's Evil Incorporated! ♪
Brendan: Well well well, if it isn't Perry the Platypus! Wait, is it seven o'clock yet? (Pauses for a beat) Now! Now you are too late. So Perry the Platypus, tremble in fear before the most twisted, nightmarish creation the world has ever known! My gun! (Shoots at Perry, who collapses and falls asleep.) I'm gonna use it to kill Phineas & Isabella! (Evil laugh)
Act III[]
Act IV[]
(Scene cuts to Candace & Ferb, who have bought the engagement ring. They're now driving back home.)
Candace: Oh, Phineas is gonna be so happy when he sees this!
(Candace & Ferb arrive back home & get out of the car. They give the engagement ring case to Phineas, who is now dressed as a groom. He rushes to the Slushy Burger. Isabella is now wearing a dress)
Isabella: Well, you're on time!
Phineas: And I thought I was late!
Isabella: Coincidence, am I right?
Phineas: Hey, waiter! Give us the tastiest least fat-saturated meal you've got! This is for you, Isabella. (opens the case) Will you marry me?
Isabella: YES I WILL! (hugs Phineas & takes the engagement ring) It looks sooo beautiful!
Phineas: Score! We'll be married tommorow, right?
Isabella: Yes, in the evening.
Act V[]
(Scene cuts to the Flynn-Fletcher house, in Phineas' bedroom, where Candace is all dressed up & has wavy hair)
Candace: Hey, Phineas, wake up!
Phineas: (wakes up) Good morning, Candace.
Candace: Oh, come on, the wedding's about to start in 5 hours!
Phineas: 5 hours? That doesn't sound so bad. Also, you look beautiful, Candace!
Candace: Thanks! But I feel like I was ready way too early.
Act VI[]
(Scene cuts to the park, where Phineas & Isabella are ready to marry each other. Their parents, Ferb, Candace, Jeremy, Stacy & the others are also present. A gunshot is heard. Candace screams.)
Phineas: Candace, what is it?
Candace: SNIPER ON THE ROOF!
(Candace was right. The sniper on the roof turns out to be Brendan, who was just testing the gun to see if it works. He installed a scope on it.)
Brendan: I've finally got you now! (Perry shows up & disarms Brendan by stabbing him in the hand) OW! MY HAND! PERRY?! (Perry shoots him with a transquilizer dart & Brendan passes out) Curse you...Perry...the Platypus...(Perry carries his body to Brendan's Evil Inc. building & leaves him outside)
(Scene cuts to the park, priest shows up)
Candace: I think the sniper's gone.
Linda: Thank God. Hey, Phineas!
Phineas: What, Mom?
Linda: Be sure to try out the cake that me & your step-dad have made!
Phineas: Of course.
(Phineas puts the engagement ring on Isabella's hand)
Priest: Alright, let's cut to the chase. Do you, Phineas Flynn, take this woman to be your lawful wife?
Phineas: I certainly do!
Priest: Do you, Isabella Garcia-Shapiro, take this man before you to be your lawful husband?
Isabella: Yes, I do.
Priest: OK then, I hereby pronounce you man & wife. Phineas, you may kiss the bride.
(Phineas & Isabella kiss, every one of the guests weep a little & smile.)
Candace: This is so beautiful!
Linda: Finally, my boy is married!
Buford: Now that's what I call a wedding!
Baljeet: Agreed.
(Phineas & Isabella stop kissing, they taste the cake.)
Phineas: Mmm, tasty.
Isabella: I love how it tastes!
Linda: Thanks! I'm glad you loved it.
Phineas: So, now what?
Isabella: I know what to do. (blindfolds Phineas) Come on!
Ending Credits[]
(Scene cuts to the Flynn-Fletcher house at late evening, where Phineas & Isabella are in the bedroom. Phineas unfolds his blindfold.)
Isabella: Surprise!
(Phineas sees his bed having enough space for 2 people to sleep in)
Isabella: Me & the Fireside Girls made it ourselves!
Phineas: That's so sweet of you, Isabella!
(They both lie down on the bed in their sleep clothes & kiss one last time)
Isabella: Good night, Phineas.
Phineas: Good night, Isabella.
(Perry appears & chatters)
Isabella: Oh, there you are, Perry!