Based on the Harry Potter and the Sorcerer's Stone (Game)
"Mr. Potter, if you would," Quirrel faced a classroom full of first years with a nervous anticipation, "crawl through this space in the w-wall, obtain the Incendio s-spell book, and return h-here to the c-classroom."
Harry hesitantly stepped forward from the crowd of eye blogging students and made his way over to the portrait in the wall. The portrait slid over to reveal a small crawl space in the wall. He glanced into the opening, noting that there were hardly any lights luminating the passage, making it anything but welcoming. He lifted himself up and into the dark passageway.
A quick "Good luck, Harry!" was shouted through the air by Hermione before the portrait slid back into its original position with a bang, blocking off any connection to the room he had just left.
Harry silently took in his environment as his vision adjusted to the darkness. From what he could see, he was in a sewer underground; the semi-circular archway hung low above him and continued on for a short distance until it sharply cut off at a fork. Harry pressed his ear against the wall he had entered from, listening for any murmuring through the wall. Harry could hear nothing that suggested there was life on the other side of the wall; the only noise his ear was able to detect was the soft tap of water dripping somewhere nearby. Magic had mysterious qualities Harry had to admit. He wondered if he was actually on the other side of the wall or if he was somewhere completely different in the castle. There was only one way to find out.
I just hope I can find my way back. Harry turned around and walked down the pathway. He drew his wand out as he turned left at the fork. The path twisted around a corner while a couple green flames flickered endlessly in their candle holder. Harry let out a groan as he drew closer to an unexpected dead end. Lumos. Harry held out his wand arm to light up the corner. Here lain in the corner was a small chest. Curiously, Harry went over to the chest, lifted the lid, and pulled out a small object. He brought it to his face and held his wand over the object. A Pumpkin Pastry! Harry didn't realize how hungry he was until the aroma of the pastry filled his nose.
He took a large bite of the pastry and turned around. He noted the familiarly of the pastry, a sweet coating of icing drizzled over pumpkin cake, and finished it in another bite. And it was warm too! Harry hadn't expected that in this seemingly damp environment. He arrived back at the fork again and started on the passage leading to the right. He traveled up a circular flight of stairs and arrived at an open doorway. He stepped out onto the wooden floor but stopped shortly as the floor sharply cut off to a drop. Harry peered over the edge of the jagged boards and saw only darkness. He wasn't sure how far the drop was. It could have gone on for ages.
Better find another way across. Harry peered to both sides of him for some kind of rope. He scratched his head when he realized he was still thinking like a muggle. C'mon, Harry. Focus. You're a wizard. Think like a wizard. He murmured limos to his wand again and watched the room light up with a low neon green glow. He saw nothing to his right as the boards caved away. Seeing nothing more promising, he flatted his back to the wall and faced his certain death. He inched his way along the wall, holding up his head and gradually moving his way to the next platform. Suddenly a couple feet away, Harry heard an unnerving sound. The wall next to him made a shifting sound and pushed out of its place, promptly taking up the little two feet of path there was. Harry held his position flat against the wall, scarcely breathing. Was the whole wall going to jolt out or was it just that portion of the wall? Harry waited for the wall behind him to push him to his impending doom, but it did not. Harry waited several more moments calming himself before realizing the pathway was making a pattern. A couple feet over from where Harry stood trembling, a portion of the wall was slowly shifting in and out of the wall by itself. Harry peered over the remaining portion of the path and noticed one more portion of the wall that shifted outwardly. Harry breathed deeply and counted the number of seconds the wall stayed put before jolting outward. …Twelve…thirteen…fourteen…fifteen—Harry stopped counting as the wall slid out, blocking his path once again.
He knew the pattern; he knew what had to be done. All he had to do was…move.
As Harry waited for his muscles to respond to his wavering command, thoughts began to crowd his mind. What if I'm taking too long? Am I really ready for this? I've lived as a muggle for so long, maybe I'm not good enough to be a wizard. Harry imagined how Dudley would react if he could see him now. He'd probably laugh and add some snotty comment about Harry being put in his place.
Harry made up his mind. If he was going to go, he was going to give it his best. He waited until the wall was inching away from returning in its position and bolted. He wasted no time sliding against the wall, keeping his back flat, and managed to not look down. He kept inching along the wall at a hurried pace until he felt the wall move again. His heart skipped a beat; he had forgotten to keep track of how much wall he had covered in his haste. A good five feet away him, the wall pushed forward. Harry let a long, deep sigh, and let his relief wash over him. He looked ahead to his left and saw the second portion of the wall that gave away close by. He could do this.
As Harry passed the second obstacle, he found himself sliding onto a solid platform. In the middle of the platform stood a lone pole with an owl craved on the top of it. The top layered off as a tray, holding what appeared to be an old book. The spell book! Harry pushed himself away from the wall and took a couple strides over to the book. He held out the book in his left hand and tapped it with his wand in his right hand.
A light breeze circled Harry as pictures arouse all around him. However, instead of seeing yellow and red flames with the subtle whisper of incendio, an electrifying blue whirl of color whizzed by Harry with a light whisper of Flippanio. Harry was confused. He had already learned Flippanio. Was this the wrong book? Had he crawled through the wrong portrait by mistake? Harry imagined Professor Quirrel's unmistakable stuttering accompanied by arisen panick at the sudden realization he had put him into the wrong passage. However, the pictures suddenly turned dark and showed a creature Harry had never seen before. It looked like a humongous desert turtle with a large spikey shell. The creature spit out fire for a couple seconds before closing its mouth. It stood there shaking its head from side to side before walking in place. The images distilled and the wind stopped. Harry stood there with returned dread. The door, which Harry hadn't noticed before, stood on the wall where Harry had first entered the platform. He went over to the door and turned the knob, slightly making a crack in the doorway. He listened to the other side of the door where he could hear faint sparking noises and something dragging.
Bloody hell.