"You can't hide from me, Potter!" Crouch Jr continued to mock him. Harry moved to a different spot, still hidden under the tables, and tried the tactic again. Just like before, Crouch Jr seemed to know exactly where he was and sent a curse his way to prevent him from attacking. 'It's like he can see right through the tables.' Harry thought as he dodged the spell. 'Of course! He can see through the tables because of the magic eye!' he realized, figuring out why he was at a disadvantage. He was going to have to change strategies. Harry knew that as soon as Crouch Jr saw him get up he would cast some spell at him, meaning that if he timed it right he could dodge and have a split second where he could fire a spell and Crouch Jr would be vulnerable.
Harry decided to try his plan and jumped to his feet. As expected Crouch Jr had already fired a spell at him, the same yellow one from last time. Harry turned to the side to avoid the curse and yelled "Accio Magic Eyeball!" Immediately Crouch Jr's magic eyeball and the harness that kept it strapped to his face flew off of him and soared towards Harry. Crouch Jr roared in anger as they eye was ripped from his face. Now, instead of having the advantage he was at a disadvantage because he only had one working eye.
"I will make you suffer for that, boy!" Crouch Jr screamed. Harry kept up the attack, firing off the first spell that came to mind he shouted "Expelliarmus!" but Crouch Jr was able to sidestep the disarming spell and cast a blasting hex at Harry which caught him in the shoulder sending him spinning down to the floor. The shoulder felt sore and Harry knew he would be in pain later but there was no time to think about it now. Harry sent off a Reducto which died harmlessly as Crouch Jr raised a shield to protect himself. Knowing that his spells probably could not break through the older man's shield, Harry yelled "Accio desk!" and the desk that Crouch Jr had been standing in front of quickly slid towards Harry. This tactic caught Crouch Jr off guard and sent him toppling backwards over the desk.
The Death Eater quickly got back on his feet and sent another blasting hex, but at the last moment Harry was able to raise a shield which was just able to stop the spell. The shield did not however have enough power behind it to stop Crouch Jr's follow up spell, a bone breaking curse which hit Harry in the left arm just below the shoulder. Harry screamed in pain as he dropped the shield spell and tried to move towards cover. His left arm now hung uselessly at his side. Harry knew he needed time to catch his breath and grinned as a spell he had learned for the first task but never had to use came to mind.
Crouch Jr was now moving around the room in order to get a better shot at Harry and was completely surprised when he saw the teenager transfigure a chair into a wolf that growled angrily and lept at him. Before he could defend himself the wolf was on him with its claws and teeth tearing into his flesh. The wolf's teeth were digging painfully into his shoulder when he managed to cast a severing charm at its head, killing it and forcing it to revert to its previous shape. As he got back to his feet Harry walked towards him and screamed "Bombarda!". The force of the spell hit Crouch Jr in the chest and sent him flying into the wall where the impact broke the wood paneling. Crouch Jr was casting a new spell as soon as he hit the ground. This time Harry raised a shield to block the yellow acid spell which Crouch Jr seemed to be so fond of. The spell struck his shield and fizzled out harmlessly.
Barty Crouch Jr was shocked, he had clearly underestimated the boy and the power he was capable of putting behind his spells. There was no way a fourth year student should be able to shield against his spells, and yet Harry Potter could do it. Growling in pain and frustration, Crouch Jr rose to his feet and yelled "Crucio!" Harry shouted "Protego!" in response, remembering at the last moment that it was not possible to shield against the torture curse but by then it was too late. As the spell hit him Harry felt like every inch of his body was being stabbed by burning knives dipped in poison. His screams of pain echoed loudly through the classroom, bringing a smile of pleasure to Crouch Jr's face. The Death Eater ended the spell long enough to taunt Harry.
"Perhaps I should drive you insane like we did to the Longbottoms. That wouldn't technically be breaking my master's command now would it?" he asked as Harry writhed in pain below him. Crouch Jr laughed and then recast the spell, enjoying the screams of pain he was causing. Neither of them knew that Harry's screams would end up saving him.
Next door Professor Flitwick was teaching Charms to a group of second year Gryffindors and Hufflepuffs. The class was progressing normally until about ten minutes into the class when the professor and all of the students froze at the sound of someone screaming out in pain next door. Without a word to the students Professor Flitwick was out of the room with his wand in hand and racing to the adjacent class. When he threw open the door he was shocked to see one of his colleagues casting the Unforgivable Cruciatus curse on a student.
"Moody! Unhand him!" the small professor yelled, causing Crouch Jr to look up in surprise. When Crouch Jr saw the other professor he knew his plans to simply Obliviate Potter were ruined. Angry that he had been discovered, the Death Eater turned and tried to cast the torture curse on the tiny Charms professor. But what Crouch Jr had forgotten was that despite his small stature Professor Flitwick was a former dueling champion and a wizard that should not ever be underestimated. The incantation had not even finished leaving Crouch Jr's lips when Flitwick began moving with a speed that must have somehow been magically enhanced. The small wizard lept from table to table, closing the distance between them and dodging every spell that the impostor who still looked like Mad Eye Moody cast. The whole time Professor Flitwick was running, jumping, and dodging curses he kept his wand moving in quick but precise movements silently casting a variety of spells.
Harry's pain had subsided enough for him to look up at the duel that was now going on. Crouch Jr was immediately forced on the defensive by the sheer number of spells being cast by the Charms professor. From his point of view it seemed as though Flitwick was casting one or two spells every second, most of which Crouch Jr was able to raise a shield against but still a few were able to penetrate his defenses. One spell set the impostors pants leg on fire while another caused his face to break out in boils. It seemed that Flitwick's strategy was to cast so many spells that his opponent had no choice but to keep his shield raised, putting him permanently on the defensive. Slowly Crouch Jr's shield was beginning to break under the constant onslaught and he knew that he would have no choice but to flee.
Crouch Jr dropped his shield and began to run towards the exit. While he did he yelled out "Incendio!" several times and was able to start a number of fires as the wooden tables and chairs burned. Flitwick's attention dropped for a second as he began casting Aguamenti, producing huge jets of water that put out the fires. In the short time that took Crouch Jr was out the door and running down the halls towards the exit. Professor Flitwick took a quick glance at Harry who was still lying on the floor groaning in pain but obviously alive before running back out the door. The Charms professor softly cursed as he walked out of the classroom, knowing that the other man had been able to escape. Looking out the window he could clearly see Professor Moody running towards the edge of the wards and away from Hogwarts. Flitwick decided there was little else that could be done about it now and went back inside to check on Harry.
"Mr Potter, I know you are in a lot of pain right now but I need to know what spells you were hit by." Professor Flitwick said once he had reached Harry, who was now sitting up and leaning against the wall trying to catch his breath.
"Other than the two Crucio's, he hit my shoulder pretty hard with something and caught my arm with a bone breaking hex. That's all." Harry explained. "Professor Flitwick, I know it looked like him but that was not Professor Moody. He said his name was Barty Crouch Jr and he must have been taking Polyjuice Potion to make him look like Moody. The real Moody is up in the office somewhere, probably being kept as a prisoner somehow."
Professor Flitwick's mouth opened in shock at Harry's explanation. He knew that Barty Crouch Jr was supposed to have died years ago in Azkaban, but if he was right then perhaps the real Alistor Moody was in the Defense Against the Dark Arts office and would be able to cooberate the story.
"Can you stand, Harry?" the small professor asked. Harry nodded and slowly got to his feet, shaking a bit as he did. After a few moments he felt confident enough to walk and the two headed towards the office. Once inside they looked around but did not see any sign of Mad Eye Moody. "Step aside, Harry" Flitwick commanded as his eyes fell on a large trunk shoved into the corner. A blue burst of magic lept from Flitwicks wand and the trunk's many locks began to open. As the final lock clicked the lid opened and they both went over to look inside. Harry was surprised to see that the space inside the trunk was huge, many times bigger than it should have been without magic. And laying at the bottom of the trunk was the real Mad Eye Moody. He looked weak and malnourished, but other than that uninjured.
"Filius? Is that you?" the true Moody asked and began to stand up.
"Wonderful to see you again, Alistor" Professor Flitwick answered. "If I lowered a ladder could you climb up?"
"Aye, I believe I could. Just get me out of here."