A/N:
I've got no inspiration for my other story, so I decided to start a new project.
The chapters will be much longer in this story. I already have the first 3 typed up, but beyond that, I have no idea what's going to happen next. If I plan a story, then I get bored and never finish it.

DISCLAIMER: I don't own any part of Phineas and Ferb.

Chapter 1.

The darkness swallowed me whole, providing the perfect hiding spot. I had been running for too long. My legs ached and my lungs burned. I didn't think I could run any longer. I needed to find a hiding spot or a way to keep going.

I reached the end of an alleyway; it was a dead end. I ducked behind some bins, my heart beating madly as if it might burst out of my chest. I heard the footsteps grow louder and closer, until they were practically right next to me. I had to bite my tongue to keep from screaming. But then the footsteps passed, getting quieter as they went off into the distance.

I don't know how long I stayed there. It could've been a few hours or a few minutes. I wasn't aware of a softer set of footsteps until they were stood right next to me. Whoever it was crouched down next to me. I could hear their heavy breathing, as if they'd run here. Their face must've been inches from mine, but I couldn't see anything in the darkness. "Phineas?" breathed a girl's voice, so soft I almost didn't hear it. I tried to back away from her, but she grabbed my hand. A second later she turned a torch, and I got a good look at her face. She had raven black hair and bright blue eyes. Something about her seemed very familiar, although I couldn't place her face. I had no memory before 24 hours ago. All I knew was that someone was chasing me. I spent the rest of the time running.

"Phineas?" she asked again, shaking my arm. I gathered that 'Phineas' was probably my name.

"Phineas? It's me, Isabella" she whispered.

"I-I don't know who you are" I stammered. A look of hurt flashed through her eyes.

"D-Don't be silly. That's not funny, Phineas."

"I'm not being funny. I really don't know you."

"Phineas? If you tell me you're joking, I won't be mad."

"I'm sorry, I'm telling the truth."

"O-Okay. So how much can you remember? Do you remember Ferb?"

"I can't remember anything before about 24 hours ago. And who's Ferb?"

"You don't remember Ferb? What about Perry? Or Candace?"

"I'm sorry, I don't remember any of them."

She was nearly crying by this point, the torch shaking in her hand.

"W-What about me? Do you remember me, Isabella?" she asked, her voice shaking.

"You seem familiar somehow, but I still don't remember you. I'm really sorry" I told her, wishing I could stop her from crying. The tears were streaming down her cheeks now. I felt like I should know this girl, like she was really important to me.

"You need to come home with me. Everyone's looking for you. Ferb hasn't spoken for the week since you went missing" she commanded, drying her eyes with her sleeve.

"No, I-I have to hide from them" I told her.

"From who? Who's after you?"

"I don't know, I just need to run."

I tried to back away from her, but she grabbed my wrist.

"Please. We can help."

I didn't know where else to go, so I nodded. She led me back down the alleyway and out into the street. The only light around was coming from the street lamps. According to the watch I hadn't realised I was wearing, it was about midnight. I was about to ask what she was even doing up at this time, when she suddenly began speeding up, heading towards a figure standing alone down the street. I caught a glimpse of the street sign; it read 'Maple Drive', which didn't ring any bells.

When we reached the figure, I got a good look at him. He was a little taller than the girl, Isabella, and he had bright green hair.

"Ferb, I found him" she breathed, letting go of my wrist. I stood there awkwardly, not knowing what to say. This boy seemed even less familiar than Isabella, although I had a strange feeling he too was important to me.

"Phineas?" he whispered, his British accent caught me by surprise. I glanced at Isabella, who was watching me. She was probably seeing if I was lying about not remembering anyone. I turned back to Ferb.

"I'm sorry" I told him "I don't know who you are."

He looked past me, to Isabella, as if to verify this was true. She nodded, looking on the verge of tears again.

"Maybe we could show him a photo album or something? That might jog his memory" she suggested. It seemed she had accepted that I wasn't lying. Ferb nodded, and she motioned for me to follow her across the road and into the house opposite.

"My mother is out all night, so no-one will find you here" she explained, as she unlocked the door. She took us through to the living room, motioned for us to stay there, and then disappeared off up the stairs.

I couldn't bring myself to look at Ferb; it made me feel uncomfortable for some reason. I looked at the photo frames on the walls. There were pictures of Isabella, and a woman who had to be her mother. There were also pictures of Isabella with me, Ferb, and a group of other kids who must've been her friends. I was hesitant to think they might be my friends too, because not one of their faces seemed the slightest bit familiar to me. I was starting to wonder if maybe this was all a big prank, or maybe if I had gone insane. People don't just randomly forget everything and everyone they know. Something must've happened to me. I heard someone clear their throat behind me. I turned around to see that Isabella was back. In her hands were a pile of photo albums. I knew that they wouldn't help recover my lost memories, but I looked at them anyway, because I didn't want to upset her further.

The first album was full of pictures from when we must've been about three or four. I assumed that I was around the same age as Isabella and Ferb. The people in the photos of the next few albums grew up gradually, until they were about a few months before now. After we finished the last album, the other turned to look at me, silently asking if any of it was familiar. I shook my head sadly, hating having to watch their faces fall.

"Ok. So that didn't work" Isabella said finally, after a long period of silence.

"Maybe you could tell me a bit about me?" I offered, wanting to be helpful. She turned to me.

"Ok. Your name is Phineas Flynn, and you're almost 11 years old. You've lived across the road from me for almost 8 years. You have a stepbrother named Ferb, and an older sister named Candace. You and Ferb have a pet platypus named Perry. Every day, you two build the most amazing and impossible inventions, and Candace tries to bust you. Ring any bells?"

I shook my head. She continued:

"You and Ferb usually hang around with me, and some of our other friends. They are Buford, Baljeet, and my troop of Fireside Girls. Oh and Irving too, but you never really classed him as a friend. My greeting to you every day is 'Whatcha Doin?', and your motto is 'Carpe Diem'. Anything sound familiar?"

Again, I shook my head. She sighed exasperatedly, but continued again:

"Everything was fine, up until about a week ago. You left your house one day and didn't come back. Everyone's been going nuts trying to find you. I think everyone's close to giving up hope."

"So how did you find me?" I asked. She blushed.

"I was going to go meet Ferb, when I saw someone running past my house. I don't know why, but I decided to follow them. It led me to you" she explained, although something in her explanation sounded off. I didn't know what to say next, so there was an awkward silence. I walked over to the curtains and pulled them shut. Then I turned to face the other two.

"So will you help me?" I asked, my tone serious.

"Help you with what?" asked Isabella.

"Help me find out who's after me, and hopefully regain my memory."

A/N: The reason I changed my name again is because I wanted to make it the same as my fictionpress account. I was LeoValdez'sNo.1Fan, and before that I was PerryForever.

I'm open to suggestions as to what happens next. Please R&R.