First to exit the secret tunnel leading to the Shrieking Shack was professor Remus Lupin. Even though he was without his wand, he was glad that at least his hands weren't tied. Following him was Peter Pettigrew, also wandless and with his hands tied in front of him. Both of them deep in their thoughts, although unlike Remus, Peter wasn't calm. He was looking much worse for wear, scared and nervously sweating.

After Pettigrew was Ron with his broken leg in a makeshift splint, and Harry who was helping him hobble along. He was being careful so as to spare Ron from putting his weight on the broken leg, and to still aim his wand at the Pettigrew's back.

The next person in the group was Sirius Black. His posture coiled like a spring, he was looking towards Peter with a hungry expression ready to strike. It made the group quite uneasy and every so often they glanced towards him fearfully. Hermione was the only exception, being the last person walking in their column, she was determined to act, steadily keeping her wand aimed at his back, a spell ready on her lips if Black were to try anything.

It had already gone dark, and even though it was June it was a chilly evening in the Scottish highlands. The Hogwarts castle was beautifully lit, a considerable distance away from them. Harry and Ron set the pace for the group and if no interruptions came it looked like the castle's warm indoors would greet them in about half an hour.

For Ron, since the adrenaline has already worn off, it was the promise of the Hogwarts' infirmary that kept him going through the pain. That thought was his sole focus, enabling him to bear the journey. For Harry it was different. He had his mind blank, going through the motions of helping Ron and keeping his wand on Pettigrew the entire time, hoping to be ready if he tried anything.

Remus' mind was buzzing with conflicting thoughts about today's events. For him, Harry, Ron and Hermione were just kids, yet they showed incredible bravery and loyalty towards each other. Ron with his broken and bleeding leg stood up to Sirius, an Azkaban escapee, that just moments before, with his huge, grimm jaws bit Ron's leg, breaking the bone, and dragged him into the Shack. Despite the pain Ron still did it to protect his friends. Even though his hope to sacrifice himself so that they could flee was in vain, as they would never leave him. His courage and character were extremely admirable in Remus' opinion.

Hermione had also tried to do the same, although in her case, she had her friends beside her, and Harry and Ron had already disarmed Sirius, Peter and him. Still she tried to warn them of the werewolf in him, despite her fear she stayed to protect them.

After these thoughts, Remus' mind centred around Harry. He thought that Harry was young, but a man of action, every bit like his father - James. Remus wasn't there at the time; having just entered the tunnel after his sprint from the castle where he witnessed a grimm savaging Ron, but he heard the sounds of fighting between Sirius and Peter in the Shrieking Shack that Harry ended, right after bursting from the tunnel into the Shack, with Hermione right after him. She closed the trapdoor and Remus missed what was said afterwards. He was glad that he picked today to return the Potter's cloak to Harry, otherwise he wouldn't have had it with him on his way to the Shack.

After walking for five minutes Hermione sneezed. Another five and Harry felt Ron starting to shiver. It wasn't even half a mile from the castle to the whomping willow, and yet still most of the way was ahead of them. After another five minutes they were only at the halfway point and their breath was starting to become visible.

-Harry, I think some dementors are nearby, we should get to the castle as soon as possible. -Remus said, a worried expression on his face.

- Yea, I'd really like to visit Madame Pomfrey now. - Ron said through gritted teeth. He was looking pale and sweaty, even his breath was starting to sound laboured.

- I'm not leaving Ron here and he can't go any faster with his broken leg. - Said Harry firmly, yet almost out of breath, by now pretty tired from helping Ron walk.

- Do you know the levitation charm? - Asked Remus.

- Yea, but I thought it doesn't work on humans. - Said Harry.

- It doesn't but there is a very similar charm, with the incantation mobili corpus. - Remus explained, showing the wand movements with his finger.

-Mobili corpus! - Hermine incanted, and shakily, slowly Ron rose into the air.

Harry and Ron both smiled at her and it was at this moment that Sirius sprung. He made a grab for Harry's wand and with barely a touch of its tip he transformed into the beastly form of a grimm. Seeing this Peter went white with fear and jumped back entangling himself with Remus and both fell to the ground. Hermione was afraid of hurting Ron and froze in place. In his grimm form, Sirius lept knocking Harry over and gone straight for Peter. Grim's jaws sunk into his flesh with a sickening wet sound. With his eyes bulging the only sound Peter made was a throaty sigh. One bite turned into another, then another. In between spikes of pain Peter weakly begged.

- Help… - Peter cried quietly.

- Sirius, stop! - Yelled Remus.

But Sirius didn't stop. Peter's blood sprayed from his muzzle. Remus tried to push Sirius away but by now his completely wet hands were not finding any purchase, with Peter lying over him he couldn't get any leverage either. Within just seconds there were bite marks all over Peter's hands and chest and Remus had his robes soaked in blood, doing all he could to prevent Sirius from biting Peter's neck. Then, in the nick of time Ron successfully cast the immobilisation charm and prevented exactly that from happening.

After a few seconds, Harry recovered, caught his breath and cast the full body bind curse on Sirius. With a finite incantatem Ron released Remus and Peter and it was time to tend to Peter's wounds.

- It hurts… I'm very cold… - Peter weakly mumbled the words out.

- Harry, he needs to get to the hospital wing as soon as possible. - Remus said quietly. - You could levitate him and we'd be there in five minutes, faster if we took it at a run.

- I'm not leaving Sirius or letting him go. You take Pettigrew, we need at least one wand available. I don't want either of them to escape. - Shaking his head, Harry said.

- Ok Harry, I'll carry Peter and we should be in the castle soon. - Remus said.

He was also really cold now but he tried not to think about it. It didn't matter, and they would soon be in the castle anyway. He hoisted Peter up piggyback style and nodded to Harry. Ron levitated Sirius, and the group was on their way again.

- Harry, something is wrong. It's too cold, it isn't normal. - Hermione said worriedly.

- You're right but we will soon be in the castle. It's just 300 yards now. - Harry replied tiredly.

- Harry, Pettigrew lost consciousness. - Remus warned.

- I'm also starting to feel faint… - Ron said, fighting to stay conscious.

- Just hold on, it's less than 250 yards now, we'll get help in a couple of minutes. I can see Hogwarts' lights flickering… - Harry said.

Then it clicked for him. What he was seeing wasn't the fire of torches merrily flickering about. Those were lights that shadows passed over blocking them from view. Then he started to hear screaming. Dementors were coming for them.

- It's the dementors! - Harry yelled. - They're coming towards us.

- We have to turn back to the Shrieking Shack Harry! - Hermione said, frightened.

- Remember our lessons, the patronus charm! - Screamed Lupin.

All of them who could, turned and started running back to the Shack. Harry was wracking his brain for happy memories but couldn't find one powerful enough. He tried to cast the charm whilst thinking of the first time he got on a broom. Nothing happened. Then he tried using the memory of his first quidditch win. That try produced only a white mist that did help them feel better and got rid of the sleepiness. They ran as fast as they could towards the Shack, but soon the mist started to fade, Harry urgently tried to think of another happy memory and nothing came to mind. Taking a worried look behind them, he saw that there, beside the dementors and the lovely lit Hogwarts castle was a silhouette in the darkness.

Harry instinctively knew what it was. With just a glance he recognised that next to the castle, near the edge of the Forbidden Forest stood Hagrid's hut and seeing it Harry realised what he needed to do to cast the charm. Memories came to him and he remembered everything that the small hut reminded him of.

Their first meeting, when Hagrid came to him in the middle of a storm to deliver his Hogwarts acceptance letter. Then he told him about magic and believed in him. He told him about his parents, who loved Harry so much they died for him. His first ever birthday cake that Hagrid made specially for him. Hagrid has given him his first ever birthday present; the best owl in the world - Hedwig and also Harry's most treasured possession; the photo album he received at the end of last school year. With those memories the happiness he felt then, came back, filled him to the point of bursting and he confidently cast with a wide smile on his face.

- Expecto Patronum! - Harry yelled.

A brilliant white stag erupted from his wand, driving the dementors away. With the dementors driven back, hope returned to the group. They stopped and turned around to watch. Harry saw that the castle was so close, and right there help and safety awaited. The cold let up and even the clouds parted letting them see everything better, the path to the castle was clearly visible before them.

- That was really something Harry, your parents would be proud. - Said Lupin smiling.

- A patronus at twelve! First quidditch and now this, you just keep on breaking records mate. - Said Ron laughing.

- This run in with the dementors was even scarier than last year's Troll incident. - Said Hermione, relieved.

- Wicked stag Harry. - Said Ron.

- Indeed. - Lupin agreed.

- Thanks. Come on guys, let's get Pettigrew to the infirmary. - Said Harry.

The group began to walk but before they even took two steps they stopped because professor Lupin hadn't moved.

- What's wrong professor? - Asked Hermione worriedly.

- We don't have time to look at the sky, let's go! - Said Ron impatiently.

- Something wrong with Pettigrew, professor? - Asked Harry.

There was no response. Harry, Ron and Hermione looked at each other awkwardly, not knowing what to say. Harry was about to ask Remus again, but was interrupted by Peter sliping from professor Lupin's back. Both of them have fallen to the ground. Remus curled up into a ball and started rocking back and forth. Sirius started panicking, barking and whining through a closed snout, still petrified.

- Oh no. - Said Hermione, completely blanched with wide scared eyes.

- What's going on? Hermione? - Ron asked quickly.

- It's a full moon. He is turning. - Said Harry, now also completely white.

- Harry, you'll have to drop the Patronus, we need to run back to the Shack! Now! - Said Ron, urging Harry to go, desperately hoping he would listen. Otherwise he didn't even dare to imagine what a werewolf would do to them.

- Mobili corpus! Run Hermione! - Harry yelled.

He levitated Pettigrew, and took off to the Shrieking Shack, keeping him in front of himself. Hermione did the same, while Ron kept Sirius between them and the transforming werewolf. Harry trusted Ron's instincts and didn't question his decision to leave Remus to the dementors. He hoped they wouldn't suck his soul out. Best case scenario they'd distract him long enough for them to run back to the tunnel. What then? He didn't know. After all, they were holding the fugitive Sirius Black. Harry wasn't sure if he was innocent. Especially now, since he almost just killed Pettigrew with his bare teeth just a few minutes ago. From his story he definitely tried to kill him before and Harry wasn't blind when he tried that again right in front of him.

There was a kiss on sight order for Sirius and since there was a chance that he was innocent of his crimes, Harry was not ok with just letting dementors suck his soul out. If Black really never had a trial, then turning him into professor Dumbledore's custody would be the right way to go about changing that. Hermione said that being the Chief Warlock of the Wizengamot he could make it happen. Unfortunately, running from the dementors also meant, they were now harbouring him from them. That probably meant they were breaking the law as well. That was bad because Harry still remembered professor Dumbledore's warning from the beginning of the year, that dementors aren't in the habit of accepting excuses. Harry hated that he had to leave professor Lupin behind but as a werewolf they maybe wouldn't consider him a target. Hopefully. From Sirius' story Harry knew that dementors treated animals with indifference, yet they still affected them. With luck the dementors would distract the werewolf long enough for them to enter the tunnel to the Shrieking Shack. From there they could go to Hogsmeade and using the secret tunnel from the Honey Duke's cellar they could double back to Hogwarts.

They were running like mad, their breaths forming into little clouds as dementors got closer and the temperature dropped again. At full sprint they'd cross the distance to the tunnel within one minute. Even with adrenaline in their veins, running on Hogwarts grounds was only a little better than running cross country. They were very lucky not to fall or drop anyone.

With 200 yards to go the dementors were starting to close in although they'd still make it to the tunnel before them.

At 150 yards to go Harry spotted Crookshanks by the knot that froze the whomping willow. With 100 yards to go the temperature was almost freezing and Harry started to hear the screams.

At 80 yards to go he heard a howl nearby.

At 60 yards to go he knew that a werewolf was coming for them.

At 50 yards remaining Harry saw that whomping willow still moved about threateningly. He wondered why Crookshanks didn't freeze it yet?

At 40 yards to go he heard the clear sounds of a werewolf running for them.

At 30 yards to go Harry saw the whomping willow draw her branches back ready to punch anyone who got close.

At 20 yards to go there was a wet smack and a sound of something connecting with a body right behind him. Then something warm splashed his back. Harry's heart was beating so fast, it was ready to burst out of his chest, the rush of blood filled his ears and his vision blurred.

At 10 yards to go Sirius was whining and yelping constantly. The whomping willow threw the first punch and Hermione and Ron got smacked with a couple of branches. They didn't stop despite the cuts and bruises. Why didn't Crookshanks stop the tree from doing that?

At 5 yards to go all of them saw that there were massive branches coming their way that would prevent them from reaching the tunnel. They could hear the werewolf being so close they didn't dare stop or even look back. As leaves and the smaller branches were starting to hit them Crookshanks put his paw on the tree-freezing-knot. The entire whomping willow froze up for the moment. Peter and Ron were first inside the tunnel, next one was Hermione, then as Harry got inside at full speed, Crookshanks beside him, he felt a warm splash with chunks hit the back of his head and spine.

At that moment Harry looked back and saw the tree coming back to life, as if it never stopped moving. With its full mass it hit. He also saw the massive hunched over figure standing there by the tunnel's entrance less than 3 yards from him. It was leaning in and reaching for him, and he realised he was within its reach. The already dripping blood right claw of a werewolf was coming towards him. It was as big as a bear's and with a body that big it'd easily cut off his head. Was he going to die?