"LOWWWWWEEEE!" The voice screeched.

Perry pressed his pillow over his head. The voice sent cold ice down his spine.

"I'm so sorry." Lowe said again. "I wish I knew how to get rid of him, but… I just don't. I've tried."

"Do all ghosts get like that on their death day?"

"I don't know." Lowe said. "I studied psychiatry for animals, not phantoms."

"He finally stopped." Perry noticed.

A loud banging sound came from outside the house.

Lowe sighed.

"What's he doing?" Perry asked nervously.

"Nailing all of his favorite objects to the outside wall." Lowe said sadly. "It takes a long time to get them off."

...

"Dead end." Flynn said.

"Nice directional skills." Fletcher said sarcastically. "I told you we should have gone to the right."

"Boys. Shut up." Agent scolded. "All we have to do is turn around."

"This is kind of cool." Phineas said, looking at the walls. "The robots have amazing technology."

"Mediocre." Fletcher said. "The kinds we have back in the future are far superior to this."

"There's better stuff than this?" Phineas asked.

Fletcher grinned. "Tons more. I've even created-"

"Which way are we going, Sir Compass?" Flynn interrupted.

"In the opposite direction you tell us to. That'll guarantee we get back on course." Fletcher replied.

Agent whacked Fletcher with his cane. "Cut it out and TURN AROUND. It's like talking to a couple of bitter walls."

They started back the way they came.

"Hang on." Fletcher said, staring at a control panel on the wall. "Something's overheated. I can tell by the screens on the wall. We'd better watch our-"

A large explosion came from the floor in front of them. Flames blasted out of the walls.

Phineas felt himself blown back. He landed, bruised, on the floor.

He forced himself to get up. A wall of flames was in front of him. Agent was next to him, trying to push himself up with his cane.

"BOYS!" Agent yelled. "You all right?"

"We can't see you. Where are you?" Flynn called.

"We may have gotten separated. I have young Phineas with me."

"I've got young Ferb." Flynn yelled back.

"I have Doofenshmirtz." Fletcher shouted.

"You still have your headsets?" Agent asked. "We may have to go in opposite directions."

"Yes." Flynn said.

"Try to find the way out." Agent said. "If one pair of us escapes, help the others get out, got it?"

"Ferb!" Phineas yelled.

"We'll meet up with him later." Agent said. "Come on."

With surprising speed, Agent pulled him down a corridor.

...

Perry woke with a start. He looked around.

Lowe had fallen asleep in his armchair, his dictionary-sized book open on the floor. Lowe's father was still screeching outside.

"YOUUUUU DARRREE LOOCCCKK MEE OUTTT OFFF YOUURR HOUSSSEEEE? MYYYY OWWWNNN SOOOONNNN, HOWWWW DAAARREEE YOOOOUUUUU?"

Perry walked over to the book and picked it up. It appeared to be a book on ghosts.

He flipped through a few pages until he found an interesting-looking section.

HOW TO GET RID OF GHOSTS:

The method of getting rid of ghosts is fully dependent on the kind of ghost you are dealing with. Ghosts generally act the same way they did in life, save for their Death Day, when they become increasingly agitated. If you are being harmed by a ghost, you may want to get rid of it.

"Ya think?" Perry asked. Outside, Lowe's father began scratching another message into the window.

TYPES OF GHOSTS THAT CAN CAUSE HARM:

CATEGORY 1: Category 1 Ghosts have the same appearance they did in life, and they are very dangerous because they can physically maim, dismember, harm, and pretty much beat a person to a pulp. They cannot kill, however. They will listen to reason. If you ask them to leave, they probably will. If they have something against you, though, they probably won't and you'll have to get rid of it by putting flowers on its grave or helping it with unfinished business.

CATEGORY 2: Category 2 Ghosts are basically a small little puff of smoke with the head they had in life. They can develop into the form they had in life, and then they will become visible to all. The small-puff-of-smoke form can be spotted if a light is shone directly on it. On the Death Day, the head enlarges to twice its size and the teeth give off a pointy appearance. These ghosts can only slightly injure people if they're really ticked off. You can get rid of it by doing the hokey-pokey or helping it with unfinished business.

CATEGORY 3: Category 3 Ghosts look exactly as they did in life and are not transparent at all. One could be your best friend, and you wouldn't even know. Category 3's are completely unaware of their death and will go on with daily life as normal. On the Death Day, they become very weary and a little confused. They have a hard time getting things done. Things will not go through them, but they can inadvertently walk through things if they do not notice them. If your friend is walking through walls, he or she is most likely a Category 3 Ghost. You must gently break the news to them and help them with unfinished business to get them to rest in peace. Please note that some Category 3 Ghosts are only half-dead. They will come back to life if the person or ghost who almost killed them is gone. They will die if the person or ghost who almost killed them completely kills them.

CATEGORY 4: Category 4 Ghosts are EXTREMELY DANGEROUS. These ghosts look like Category 1 Ghosts on any day save for the Death Day. On the Death Day, the eyes become large and red, almost reptile-like. The mouth is permanently fixed into a sharp-toothed smile that stretches across the entire face. DO NOT COME INTO CONTACT WITH IT. These ghosts can split up a being into two, slowly drain the life from a being, and cook amazing pancakes. If one physically cuts you, there is no hope. If one kills you, there is also no hope (You probably could have figured that out on your own, though). The only way to get rid of these is to remind them of their loving nature (if such a nature exists) or help them with unfinished business. BE EXTREMELY CAREFUL.

Perry kind of had an idea of which ghost they were dealing with. But he had to be certain.

He took Lowe's glasses off and put them on his own face. Then, very slowly, he pulled back the curtain on the window.

A little transparent fennec fox with unblinking red eyes stared back at him. It had a hideous grin that the Cheshire cat would have envied. The sight made Perry's heart nearly stop in fear.

"HiiiiiiiiiiiiiiIIIIIiiiii." The ghost said, barely opening its mouth to get the words out.

The scratched words HI LOWE were all over the window.

Perry tried to stop himself from shaking. "He…hello… w…what have you been doing?"

He hoped that the ghost would calm down if someone talked to him, or perhaps even become a little normal.

"Iiiiiiiiiiii am writttinng." The ghost said. "IIiiiiiiiiii ammmmmm."

"P…please let us help… you." Perry stuttered. "Don't harm Lowe anymore… he's y-your son, your son. You w-want to help him, don't you?"

"HAAAPPPPPYYYY DEEEATTTHHHHH DAAAYYYYY TOOOOO YOOOUUUUUUUUU!" The ghost began to sing in a horrible screech. "HAAAPPPPYYY DEEEATTTHHH DAAAYYY DDDEEEAAARRR LOOWWWWWEEE!"

Perry wondered how Lowe was sleeping through his father's song. He removed Lowe's glasses. Not being able to see the ghost calmed him down a little.

"Do you have unfinished business?" Perry asked.

"Whhhyyyy yeesss! IIiiii neevverrr finiishshheedd killliinnggg himmm!"

"You're not killing Lowe." Perry said sternly.

"LOOOWOWWWEEEEE!" The ghost squealed.

Perry noticed something out of the corner of his eye. A music box was nailed to the side of the house.

"Do you like music?" Perry asked.

"Mussic?" The ghost asked in a soft voice. It went back to full volume in another second. "LOOOWWWWWEEEEE!"

Perry grabbed a music box from Lowe's coffee table and brought it back to the window. He wound it up.

It began to play a cheerful tune. The ghost's screeching fell silent.

Perry put Lowe's glasses back on.

The ghost no longer looked terrifying. It looked like a normal fennec fox. Its eyes were wide.

"Music…" He said softly. "Music… I like music…"

His eyes focused on Perry.

"Thank you." He said. "Thank you for saving my son."

He vanished in a thin stream of smoke.

Perry heard movement in the room. He looked over at Lowe.

Lowe was sitting up in the armchair. His eyes were wide.

"Never underestimate the power of a music box." Perry said.