Ferb makes a thumb up for Phineas.
Phineas: Great, now we can test our giant-beam!
Suddenly, a purple light comes from nowhere. It appears to be the Time-Machine Phineas and friends build. Someone is sitting in it... but who?
Phineas: Who are you??
Future Phineas: I'm you, but from the future!
Phineas: Wow... hey, what?
Future Phineas: You have to come with me, Phineas! Your's and Isabella's future kids are in danger!
Phineas and Isabella: SAY WHAAAT?!
Phineas and Isabella stare at each other.
Future Phineas: Come on! We don't have much time!
Phineas: Wait, how about Ferb?
Future Phineas: We can't! We have to have only you two, Phineas...
Ferb: I understand. Hurry up, Phineas!
Phineas hugs his bro and then takes Isabellas hand.
Phineas: Come on, Isabella! We have a future to save!
Future Phineas, Phineas and Isabella leave with the time-machine leaving Ferb, Baljeet and Buford alone.
Ferb: ... that was actually weird.
Buford and Baljeet: Yes, yes it was.
Ferb: Come on... we have a giant-beam to test!
Meanwhile... or at least, 30 years in the future...
Phineas: Wow, this place is sooo...
Phineas and Isabella: ... hi-tech.
Future Phineas: Your future kids are Julia, Jacob and Angela. They are about the same age as you guys.
Isabella: I always loved the name Angela...
Future Phineas: It's time to meet my wife, Isabella.
Phineas, Future Phineas and Isabella walk to a cute yellow house.
Future Phineas: Izzy? Are you here? I brought ourselves!
Future Isabella: Hi me! Hi Phineas!
Phineas and Isabella: Helloo... eheheh...
Phineas: Wait, you never told about our kids, what's the problem with them! Tell me, me!
Future Phineas: Okay, here's how it goes. The kids are just as you guys were. But the problem is, Jacob are gonna build a laser-beam! I tried to tell him that it's dangerous and he could hit the wrong stuff, but he wont listhen to me. So here's your job: You guys convince him that it's dangerous and then give him ideas that are off things that you guys build... like that rollercoaster, niagra-falls,a backyard beach... think you can handle it, Isabella and Phineas?
Isabella: Bring it on!
Future Phineas: Thanks. Okay, I'm gonna go in the house so I won't disturb you guys. See you, and good luck!
Future Phineas leaves.
Isabella: Uhh, Phineas?
Phineas: This is so weird...
Ïsabella: But we are togheter, remember?
Phineas: You're right, as always, Isabella.Phineas hugs Isabella and then takes her hand.
Phineas: Let's meet our kids, Izzy!
Isabella and Phineas, holding hands, goes to the backyard. They see two girls and one boy holding something.
Jacob: Hey, watcha guys doin'?
Angela: Is that my twin?
Julia: Who are you guys?
Phineas: We are from the past. We are your young parents.
Jacob, Julia and Angela: No way!
Julia: Cool! What brings you here, mom and dad?
Phineas: Hey hey hey, wait a minute! Don't call me dad, it makes me feel old! Call me Phineas.
Isabella: Yea, call me Isabella.
Julia: Okay... uhh, Phineas and Isabella, what brings you here?
Isabella: It's the stuff your building! Jacob, what do you need a laser-beam, anyway?
Jacob: ...it's cool.
Phineas: I can't belive your my kid. Okay, have I told you about the cool stuff I made?
Jacob, Julia and Angela: Yeah, duh, your our dad.
Phineas: We made that stuff because it was fun, and to make every day of summer to count. Not to impress people with some scary cool stuff, no.
Jacob: But I think this is... fuuun...
Isabella: You know what, Jacob! I'm just gonna take your little toy now, and then your gonna listhen to Phineas.
Angela: That's soo mom-style.
Isabella rolls her eyes and snatches the laser-beam from Jacob.
Phineas: Now, what would you like to build today?
Jacob: A laser-beam...
Phineas: Exept that.
Julia: Can't we build a rollercoaster, like you guys!
Angela, Phineas, Julia and Isabella: Let's do it!
Jacob: All right!
Phineas: Actually, I can belive your mine kid.
Phineas and Isabella tells the kids all about building a rollercoaster, he warns them that everyone is gonna ask if they aren't a bit young to build it, then what stuff they need and the design on the rollercoaster. Only some hours later, it's done!
Phineas: Nice work guys! Izzy, can you do me a favor and pull that leaver?
The van goes up and up and up with the kids, untill they could touch the moon.
Everyone: You betcha!
The van rides the rollercoaster.
After the ride.
Phineas: Was that not much funnier then an old laser-beam-thingy?
Jacob: Yeah, you're right... Hey, Julia, Angela! Tomorrow we can make the world largest cookie!
Phineas (to Isabella): Well, Izzy, our work here is done!
Isabella: See you, in like 20 years or something!
Jacob, Julia and Angela: You betcha!
Phineas and Isabella tells first the future themselves about the mission succes, and then they eave with the time-machine.
Phineas: Hey, where's Ferb?
Isabella: Uhh, Phineas?
Giant Ferb: Oh, you guys are back.
Giant Baljeet: Let's shrink!
Buford, Ferb and Baljeet shrinks to normal size.
Phineas: Awsome, let me try! Izzy, come on!