Trope Bingo: time travel. Two different styles!

T rated for strongly implied off-screen sexual activity, but nothing explicit.

Thanks to Axis22 for giving me this idea. (Or, alternately, blame Axis22 for giving me this idea.)

I'm not willing to state that this is in the continuity for Back in Time for Dinner and Something Special...but I will note that it doesn't exactly contradict anything there.

Timeline: summer before freshman year of high school. (If this were in the Back in Time for Dinner timeline - and I'm neither saying that it is nor that it isn't - it would be about a year before that story. Phineas and Isabella are not dating yet. Isabella is fifteen, Phineas is a few weeks before his fifteenth birthday.)

"Ferb, remember the time we milked cows on the moon?" Phineas asked, leaning against the tree in the backyard of the Fletcher-Flynn house.

Ferb nodded.

"And the time we built an animal translator?"

Ferb nodded.

"And the time we built an aircraft carrier in Danville Lake?"

Ferb nodded.

"And the time we went back in time?"

"Which one?"

"I wish we could relive some of those times again. That's it! Ferb, I know what we're going to do today!"

"Hi, guys. What'cha doin'?" Isabella asked from the gate.

"Hi, Isabella! We're building personal time viewers so we can look back at the cool things we've done in the past."

"That sounds neat. Can I get one too?"

"Sure thing, Isabella."

Isabella looked around. "Hey, where's Perry?"

"Ah, Perry the Platypus! I see you got caught by my trap this time!" The evil scientist Dr. Doofenshmirtz gestured toward the steel cage that had sprung up from the floor to contain the monotreme agent. "You see, I realized that there's always one little flaw in my plans to take over...The Entire Tri-State Area! And if I could fix that one little flaw, then my plans would work. So I thought to myself, what if I made an -inator that would jump me back in time and let me fix whatever went wrong?" He glared at the platypus. "I know that look, Perry the Platypus. Ha, ha, I'd need to go back to before I was born. Do you mind? I'm trying to monologue here.

"Aaaaanyhow, I built this device to help me fix that one little flaw. For example, I had a strong urge to make sure there was a trap right where you are, so I'm guessing that this is the 'fixed' timeline from where I didn't trap you properly and you tried to blow up the -inator.

"So, behold, the Try-It-Again-Inator! See, there's a little counter here showing how many times it's been activated. So it should read 'one' since I added that trap. And, see, the counter says...seventeen? That can't be right. I can't have had seventeen problems, can I?"

Perry nodded.

Doofenshmirtz smiled sarcastically. "Your confidence in me is touching, Perry the Platypus. Truly. Fine, be that way. See if I care. Even if I make another mistake - unlikely as it is that I would make eighteen different mistakes - I can just use the Try-It-Again-Inator to fix it."

After an unwise comment by Buford, the time portals had been set so they could only track the person using them. Isabella skipped to some of her favorite times when they were younger - going through the haunted house holding hands with Phineas, dancing with him after the around-the-world trip, being caught by him as the Beak, the school art project where Phineas had made a gorgeous drawing of her. Someday, we'll be together, Phineas. I know it.

That raised an interesting question - he'd said these could go back in time, but what was stopping them from going forward? Isabella looked at the time controller. The dial on it only went one way. She popped the lid off and looked inside. I wonder... She reversed the wiring to the dial, and re-closed the lid. Let's try...six months forward. I can see if it's last year in school, or next year.

The screen showed her in a class she didn't recognize. That must be freshman year. Next year. It worked.

I wonder if I end up with Phineas. Let's go forward three years.

She saw herself at age seventeen. I get breasts!

Someone was knocking on the door to her house. She saw herself opening the door, and Phineas was there. Ooh. He looks so mature. So handsome.

And then she saw herself drape her arms around Phineas's neck and kiss him deeply. Her eyes got wide as she saw him returning the kiss. They said something to each other, and she closed the door to her house and led Phineas up the stairs to her room.

Phineas kisses me! He comes over to my house just to kiss me!

The Phineas and Isabella on her screen were up in her room now, and she saw that they were doing more than just kissing; her jaw dropped. The two of them were lying together on her bed, and future-Isabella had just taken Phineas's shirt off.

Phineas...and I...oh my. I guess he wasn't coming over just to kiss me after all...

She felt like a voyeur watching herself and Phineas, but couldn't tear her eyes away.

Phineas looked over at Isabella, who appeared to have turned beet-red. I wonder what she's seeing that's making her that embarrassed?

He checked the time marker for her panel on the master console. It read "+3y0d0h0m0s". Three years in the future? How'd she manage that?

If she's that red, I'm probably involved somehow. Maybe I should take a look to see what we're doing.

He quickly reversed the wiring for his controller, and set it to match Isabella's.

...oh. Oh my. He'd turned even redder than Isabella.

Isabella...um...grew up nicely. And...um...out.

I guess we do end up together.

Perry broke loose from the cage and leapt toward the evil scientist.

"Ha-hah, Perry the Platypus! Now I just need to activate the Try-It-Again-Inator again...okay, it'll be time number twenty-three, but this time will be the last one!" Doofenshmirtz shouted. He pressed the button on the remote for the -inator, and the beam hit him squarely. Time rewound...

Phineas turned off the screen and reset it to 'now'. He'd decided that he'd seen enough already, and really didn't want someone to look over his shoulder and see what he was looking at, especially since future-Isabella had been taking her shirt off at the end. He looked over at Isabella, seeing that she had apparently just done the same; she looked up at him, saw his eyes on her, and quickly looked away, blushing. I think we need to talk about this, he thought, or it's going to mess things up between us.

He walked over to Ferb and said, "I feel like we've gone forward in time before - maybe more than once - and it's always a bad idea. I need to remember that, because we keep making that mistake and then probably having to go fix it so it didn't happen. Which would be why we keep forgetting it."

Ferb nodded.

Phineas continued on to Isabella. "Uh...hi," he said. "I...saw what you were looking at."

Her eyes got wide. "But how...oh. You were there." She blushed bright red.

His own face felt hot as well, but he had to keep going. "I know that's the future, and we're not ready for anything like that now. But..."

Her eyes widened even more, and she seemed to be holding her breath.

"...whatever we're destined to do later, I think right now, I'd like to just spend some time with you. As friends. Or...maybe more than friends?"

She exhaled, and a smile spread across her face. "Really?" she asked.

"Really," he said.

She almost tackled him in a hug.

"See, Perry the Platypus! I put another trap there, because I knew that the first three wouldn't keep you! The Try-It-Again-Inator really works!" Dr. Doofenshmirtz said. He glanced at the counter on the side of it. "Even if it does take me thirty-five tries to get it right. Sheesh, this evil science work is harder than you'd think."

As he was distracted by the counter, Perry freed himself from the trap - it was a fairly basic leg trap, which he hoped Doof didn't expect to hold him for long. Perry looked around for something he could use, and spotted it over on a nearby counter. He leapt away from Dr. Doofenshmirtz.

Doof saw the movement out of the corner of his eye, and said, "Ah-hah! Now I can use the Try-It-Again-Inator to find a way to keep you trapped there!" He pushed the button on his remote again, only to have Perry jump in front of him holding a mirror. The greenish beam bounced away out the window harmlessly.

"Hey, that's no fair, you totally stole my try-it-again beam there. I'll just have to fire another one...hey, no, don't hit the self-destruct button!"

The Try-It-Again-Inator self-destructed as Perry the Platypus parachuted away.

"You know, adding that self-destruct button is the one mistake that I can't undo. CURSE YOU, PERRY THE PLATYPUS!"

Ferb looked at Phineas and Isabella. She'd hugged him suddenly, and now they were standing there holding each other. Neither of them were paying any attention to anything but each other; their eyes were closing as their mouths inched closer to their first kiss.

A green beam from the heavens came down, hitting Ferb squarely, and time skipped backwards...

"So these screens will let you see back in time!" Phineas said.

"That's awesome! I can go back to last Friday and peek in the girls' shower at school!" Buford said.

Baljeet put his head in his hands. Gretchen lightly punched Buford in the arm.

Ferb adjusted some wiring, and said, "You can only go back and see your own timeline."

He looked off into the distance for a moment, as if a sudden inspiration was hitting him. Again, he reached in and carefully adjusted the wiring of the central console. "And you can only go back in time, not forward at all."

Isabella sighed, not sure why she was disappointed, but having the odd feeling that she'd just had something taken away from her. From the puzzled look on his face, Phineas was feeling the same way.

Oh, well. At least I can go back and see all the cool things Phineas and I have done together.

The scene that Isabella and Phineas see bears a striking resemblance to Chapter 4 of Something Special. (Note: M-rated story, as you might guess.)