A/N: So, I decided to write a Phineas and Ferb fanfic. :D I don't own Phineas and Ferb, or any of the characters related to the show. Enjoy!

Isabella was in the backyard of the Flynn-Fletcher residence, lounging under the tree. Baljeet and Buford entered the backyard.

"Hey, Isabella," Buford greeted.

"Whatcha doin'?" Baljeet asked, in his thick Indian accent. Isabella gave him a deadly glare.

"Phineas and Ferb are out of town, so I'm Perry-sitting," Isabella responded, closing her eyes as a gentle breeze blew across her face.

"Who are you Perry-sitting?" Buford asked. Isabella opened one eye, raising an eyebrow at him.

"Perry..."

"That's what I thought," Buford said.

"It's sure going to be boring without Phineas here today," Isabella sighed.

"And Ferb," Baljeet added, as he and Buford sat down next to her under the tree.

"Yes, and Ferb." There were several moments of silence.

"Say, Isabella," Buford spoke up. "Wouldn't you need Perry in order to Perry-sit?" Isabella and Baljeet looked around the yard in confusion.

"Good question," Isabella agreed. "Where is Perry?"

Perry the Platypus wandered to the side of the house. He made sure no one was watching, then stood on his hind legs, and slapped his fedora on his head. He went to the flower bed, and a trapdoor sprang open, covering the platypus in dirt. He gave an unamused chirp, and jumped down the transportation tube that led to the secret HQ.

"Good morning, Agent P," Major Monogram said, as Perry brushed a weed off his shoulder. "Doofenshmirtz has been awfully quiet lately. We find that very suspicious. Find out whatever it is he's not doing and put a stop to it!" Perry saluted, and was gone.

"Perry!" Isabella called, as she and Baljeet wandered around the backyard.

"Perry the Platypus!" Baljeet called.

"Where is that little semi-aquatic, egg-laying mammal?" Isabella asked no one in particular hands on ever hips, and looking around the yard.

"That is a question that has been on my mind since the first time I saw him wander off," Baljeet said.

"That's it!" Isabella exclaimed, slamming her fist into her open palm. "Buford, Baljeet," she turned to the two boys. "I know what we're going to do today!"

"Eh, it's not the same not coming from Phineas," Buford remarked, dropping out of the tree.

"With that I have to agree," Baljeet added. Isabella ignored their comments.

"We're going to answer the age-old question!"

"What is the meaning of life?" Baljeet asked.

"No..."

"What came first, the chicken or the egg?" Buford suggested.

"No."

"If a tree falls in the forest, and no one is around to hear it, does it make a sound?" Baljeet said.

"No!"

"How much wood would a wood chuck chuck if a wood chuck could chuck wood?"

"NO!" Isabella growled in frustration.

"Then what?" Baljeet asked.

"Where's Perry?"

"Ooohh!" the boys said at the same time.

"Come on," Isabella said, waving her arm telling them to follow. "We've got some investigating to do."

"What did come first?" Baljeet asked.

"I say the egg," Buford answered, as they followed the girl. "That's a breakfast food."

"Now," Isabella said, hand on her hip, and finger at her chin. "What could Perry be doing everyday, which makes him disappear for hours at a time?"

"Napping," Baljeet said.

"I bet he's a secret agent, with a really cool fedora, who fights a nemesis who wants to take over the Tri-state Area!" Buford exclaimed. Baljeet shot him a glare.

"That is a ridiculous theory," the Indian boy said irritably. "Perry is a mindless, semi-aquatic, egg-laying mammal with no intelligence."

"That's my theory, and I'm sticking to it," Buford said stubbornly, crossing his arms. Isabella simply rolled her eyes and began the search.

A/N: Please review!