Phineas and Ferb were walking down the street towards their house after a long day at school. The last day of school before any vacation always seemed long, but the one before the summer vacation always felt the longest. The two boys were discussing what adventures the holidays might hold and what kind of things they might do to pass the long summer days.
The Tri-State Area where the step-brothers lived typically had summers filled with warm sunny days but just as they reached home they began to feel drips of rain on their faces. They rushed inside to find their sister Candis talking to their mother in a rather annoyed tone of voice.
"But Mom," she was saying "it can't rain tomorrow, I'm supposed to be meeting Stacy at the beach in the morning!"
"I'm sorry dear, but I don't control the weather. The weatherman on the TV said that it is to rain all week but after that we should have a lovely sunny summer. Even warmer than last year's apparently."
Phineas looked at Ferb as they went on to leave their school stuff in their room. Ferb nodded in reply to the look then went to his desk and started rummaging in the drawer while Phineas lifted a communication device, which he and his brother had made at Christmas, and flicked the switch. A short burst of static emitted from the speaker on the front followed by a voice.
"Phineas?" It said, "Is that you?"
"Hey Baljeet, yeah it's me, and I know what we're going to do today."
"Wow that was fast. I'm only just home, I don't think I can come over just now because it's raining."
"That is what gave me the idea. We are going to build a weather machine to stop the rain."
Ferb had found what he was looking for and was spreading the blueprints out on the desk. At the top in large letters it read "WEATHER MACHINE" and under the title was a diagram of a very complex looking machine. Phineas told Baljeet the list of items they needed and the voice from the communicator confirmed that he would get them all sent over soon.
Meanwhile Perry, Phineas and Ferb's pet Platypus, pulled out a hat and knocked on the end of Ferb's bed Three times and a hatch opened in the wall beside him. He jumped in and the hatch disappeared as fast as it had appeared.
"Hey, what was that?" Phineas asked, "Where's Perry"
Perry zipped down the tube, which resembled a water slide tube without the water. It lead to a secret government base situated under the Flynn-Fletcher family home where Perry lived. The tube deposited the platypus on a red revolving chair in front of a large monitor which the moustached face of Major Monogram upon it.
"Thanks for dropping in Agent P" said the Major. "Doofenshmirtz is up to something. He has just received delivery of parts which Karl assures me can only be made into a simple heater."
The Major's young assistant appeared on screen.
"It's true, the list of items in the delivery are exactly the same as the ones I got yesterday" Karl said before moving back to what he had been doing before his name was mentioned.
"Knowing what Doofenshmirtz has got up to in the past, I want you to investigate. Let's hope he's just cold, but we're sending you in just to be sure. Good Luck Agen…t"
Before Major Monogram could finish his sentence, Perry had left swiftly to complete his mission before he was noticed to be missing by the unusually clever boys he lived with.