He had it all planned out.
He could remember the way to Gryffindor Tower like the back of his hands. His Hogwarts days may seem as distant as past dreams, but he would never forget the happiness and wonder the castle brought.
Now however, he felt dread.
So much could go wrong here. He could get in and find Dumbledore there. That would not go well. Or the other teachers. If any were alerted to the fact that mass murderer Sirius Black was found in the castle, he couldn't take on all the teachers.
He did know that, as far as he could tell, there were no dementors inside the school grounds. With any luck, all the pupils would have already returned to their dormitories. He would be able to sneak up to the dormitory he needed. He wouldn't have to worry about five or six teenage boys, all of whom were probably fast asleep in their beds.
Sirius paced the Shrieking Shack until the sun went down and the Scottish countryside was swallowed by the autumn night. He then transformed into Padfoot and trotted down through the tunnel, into the grounds.
Dodging carefully though the flailing branches of the Whomping Willow, he made his way to the door of the castle. Through the doors to the Great Hall, he heard the unmistakeable noise of a feast.
The large black dog edged closer to the slightly ajar doors. He glimpsed a flurry of bats and hundreds of candle lit pumpkins, before he continued his journey to Gryffindor Tower. So, it was Halloween. Padfoot amused himself for a second, remembering Halloween feasts during his time at Hogwarts. They had all ended in some huge prank in the Great Hall after the feast. They always had detentions all through November for them, but it was worth it.
As he headed up through a secret passage with a trick step half-way up, he heard a wheezy voice and some shuffling footsteps.
"That Peeves!" the voice yelled "Don't worry, my sweet, I'll tell Dumbledore, he'll have to have him out for this!"
Padfoot jumped slightly as the care-taker Argus Filch stormed through the tapestry at the top of the stairs. He had the same long hair, however it was thinner and greyer than it had been, and he was wearing the same old brown coat he had when Sirius had been at the school.
The black dog froze; he knew that Filch would catch him out here. He had nowhere to run, he would surely be kicked out of the castle; dogs weren't allowed in.
As Filch turned his head to face down the stairs, not noticing the dog in the darkness, Padfoot began to slowly climb. He had to be silent; he didn't want Filch to notice him.
Luckily, Filch seemed to be annoyed about something the poltergeist had done, and wasn't paying attention to what was happening around him. Resulting in the wheezy man to forget about the trick step, his leg sunk into it and held him there. He would be unable to get out without assistance. Sirius had a hug desire that his best friend, James had been here to see this. Padfoot stopped himself from barking in pleasure at this amusing scene, Filch with his leg painfully caught as he flailed his arms and yelled for help.
Padfoot exited the corridor and carried on to Gryffindor Tower.
He managed to dodge Peeves, who had cackled loudly at the dog and tried to command him to "leave a present" for Filch on the carpet. Padfoot gave an audible growl, and Peeves zoomed off in the direction of Filch's shouts.
As he reached the portrait of the fat lady he transformed into a man.
"Password?" The fat lady asked curtly, not looking at him properly.
"Just let me in." Sirius hissed.
"No one gets in without the password." The fat lady replied, calmly.
"I NEED TO GET IN!" Sirius yelled; his patience very limited.
The fat lady jumped, and finally looked at him, she gasped.
"S-Sirius Black!" She muttered, looking frightened. Good, perhaps now she'll be too scared to deny him entry. "No. No, you can't get in. I won't let you in. No password, no entry."
Even through his anger, he had a new found respect for the fat lady; he had never known she was so brave.
However, this did not stop him from reaching into his robes and bringing out his knife. He slashed the portrait, as the fat lady screamed and ran from it.
He had done it now. Soon everyone would know he was in the castle. Sirius transformed back into Padfoot and sprinted from the scene, which was already beginning to attract attention.
He sprinted down the hidden corridor; Filch had disappeared now, and flew through the tapestry. As he neared the Oak Front doors, however, he saw something that made his heart stop.
The brown-haired man was running towards the commotion. His brown hair was greying and his face was more lined and scarred, but he was still the most beautiful man in the world in Sirius' eyes.
After a very long second, Padfoot turned from the scene, which the other man had already left. It took all of Sirius' strength to run back to the Shrieking Shack after this. Once he did get back, he collapsed in a heap of misery on the old bed.
But, at least now he knew that the brown-haired man was safe.
If you've already read this and realised that two chapters have been swapped around, that was my fault, I put them up in the wrong order... sorry!