Disclaimer: I do not own the Sherlock or Harry Potter series. This crossover is for fun.

Summary: Harry Potter's first year at Hogwarts with Sherlock and John.

Year One

Chapter 1 First Meeting

John Watson stood in the middle of the platform, staring at the scarlet engine that would take him somewhere he had never been before. John was seven when he found out he was not like the other kids. He had magic.

"All aboard," a man yelled.

John took a deep breath and entered the train. On the side it read The Hogwarts Express. It would take him to Hogwarts School of Witchcraft and Wizardary. All the compartments seemed to be occupied. Then John came upon a compartment that held only one student. It was another boy with curly dark hair. He did not seem to notice John walk in. His eyes were open, but he looked deep in thought. John thought this was strange as he sat.

"Will you please keep it down?" the boy asked.

"I didn't say anything," John said.

"You're thinking. It's distracting," the boy replied. And then the boy really looked at John. "You're a half-blood."

"Sorry?" John asked.

"When your father found out, he left," the boy said.

John's eyes grew in amazement.

"How could you possibly know that?" he asked.

"Your clothes," the boy replied as if it had been obvious. John examined the clothes his mother had picked out for him to wear. "Obviously your mother dressed you to impress."

"I was six, maybe seven when I began to show signs of magic. My mother couldn't keep it a secret," John said.

He was surprised at he had just said that to a complete stranger.

"So, what House are you hoping to be in?" the boy asked.

"You tell me," John said sarcastically.

The boy gave him a long stare.

"I don't know everything," he replied.

"I could be in Gryffindor. Mum was. How about you?" John asked.

"Ravenclaw. Although, my brother tells me I'll be in Slytherin," the boy said.

John then stuck his hand out and extended it to the boy, who looked at it for a moment with suspicion.

"I'm John Watson," he replied.

Slowly, the boy took John's hand and shook it.

"Sherlock Holmes," he said.

A knock came at their compartment door. A girl, first year by the looks of it, walked in. She had very bushy brunette hair.

"Sorry, but have either of seen a toad? A boy named Neville has lost one," she asked.

"No, we haven't," John told her.

She nodded and left.

"Muggle-born," Sherlock commented.

"Excuse me?" John asked.

"It's obvious. Already in her school robes. Over excited," Sherlock said.

For some reason, this reminded John of something.

"Oh," he said. "Hey, have you heard Harry Potter's a first year with us?"

"I have," Sherlock replied, sounding not at all interested.

It began to get darker, and soon the train was stopping.

"Here we go," John said.

They quickly put on their school robes. John could swear he saw Harry as a very large man told them to get into boats to cross the water to the castle. According to Sherlock, he was the groundskeeper and took care of the creatures. They were greeted at the entrance by a tall, black-haired witch in emerald green robes.

"The firs' years, Professor McGonagall," the groundskeeper said.

"Thank you, Hagrid," Professor McGonagall replied. "I will take them from here." The walls were lit with flaming torches. Professor McGonagall led them to a small, empty chamber off the hall. "Welcome to Hogwarts. The start-of-term banquet will begin shortly, but before you take your seats in the Great Hall, you will be sorted into your Houses. The sorting is a very important ceremony because, while you are here, your House will be something like your family within Hogwarts. You will have classes with the rest of your House, sleep in your House dormitory, and spend free time in your House common room. The four Houses are called Gryffindor, Hufflepuff, Ravenclaw, and Slytherin. Each House has its own noble history and each has produced outstanding witches and wizards. While you are at Hogwarts, your triumphs will earn your House points, while rule-breaking will lose House points. At the end of the year, the House with the most points is awarded the House Cup, a great honor. I hope each of you will be a credit to whichever House becomes yours. The sorting ceremony will take place in a few minutes in front of the rest of the school. I suggest you all smarten yourselves up as much as you can while you are waiting. I shall return when we are ready for you."

The bushy-haired girl began whispering to herself. Harry was talking to a red-haired boy. John figured it had to be a Weasley because all that family had flaming red hair. At that moment, ghosts went past them as Professor McGonagall rejoined them and took them to the Great Hall. Inside, candles floated in midair.

"Bewitched obviously," John said, referring to the candles.

Sherlock looked over at him and just nodded. John remembered reading about it in Hogwarts: A History. A stool with a patched and frayed wizard's hat sat in front. Of course John knew how they were to be sorted. By putting on that old hat and waiting for it to shout out the House they were to be in.

"When I call your name, you will out on the hat and sit on the stool to be sorted. Abbott, Hannah," Professor McGonagall said. The blonde with pigtails became the first Hufflepuff. Susan Bones also became a Hufflepuff. Terry Boot was the first Ravenclaw. Mandy Brocklehyist also became a Ravenclaw. Lavender Brown became the first Gryffindor. Millicent Bulstrode was the first Slytherin. Justin Finch-Fletchley became a Hufflepuff. Seamus Finnigan, a sandy-haired boy, became a Gryffindor. The bushy-haired girl, whose name was Hermione Granger, was sorted into Gryffindor. "Holmes, Sherlock."

John noticed a boy from the Ravenclaw table sit up a little straighter with interest. That must have been Sherlock's brother.

"RAVENCLAW," the hat shouted.

Neville Longbottom went to Gryffindor. Moray MacDougal went to Slytherin as did Draco Malfoy.

"Potter, Harry," Professor McGonagall called.

The entire room began to whisper. John watched as the small dark hair boy with glasses and a lightning shape scar on his forehead. The entire Gryffindor table cheered when the hat shorted Harry into their House.

"We got Potter! We got Potter," twins yelled.

Dean Thomas also joined Gryffindor. Lisa Turpin became a Ravenclaw.

"Watson, John," Professor McGonagall called.

He took a deep breath as he sat on the stool and placed the hat over his eyes.

"You have a very brave personality. Also very loyal to those you call friends," John heard the hat say.

"So, Gryffindor or Hufflepuff?" John wanted to ask out loud.

"GRYFFINDOR," the hat yelled.

John breathed a sigh of relief. He took the hat off and joined his House. Ronald Weasley, like the rest of his family, became a Gryffindor. Blaise Zabini was a Slytheirn. The Headmaster of the school, Professor Dumbledore, stood up. What stood out the most to John was the half-moon spectacles and the purple robes he wore.

"Welcome," Professor Dumbledore said. "Welcome to a new year at Hogwarts. Before we begin our banquet, I would like to say a few words. And here they are. Nitwit! Blubber! Oddment! Tweak! Thank you."

No one said anything as he sat. Food then appeared on the dishes. The House ghost, Nearly Headless Nick, had a conversation with Harry and others around him, but John could not hear what it was about.

"I'm half-and-half," Seamus said in between his bites. "Me dad's a Muggle. Mum didn't tell him she was a witch 'til after they were married. Bit of a nasty shock for him."

This felt very familiar to John's own story. Neville had to tell his story of how he did not even know if he would have magic.

"Ouch," someone yelled out.

John noticed that it was Harry as he placed his hand on his forehead. He did not have much time to think about it when Professor Dumbledore as he stood back up.

"Ahem – just a few more words now that we are all fed and watered," Dumbledore said. "I have a few start-of-term notices to give you. First years should note that the forest on the grounds is forbidden to all pupils and few of our older students would do well to remember that as well." He gave a look towards the twins who had yelled earlier. "I have also been asked by Mr. Filch, the caretaker, to remind you all that no magic should be used between classes in the corridors. Quidditch trials will be held the second week of the term. Anyone interested in playing for their House teams should contact Madam Hooch. And finally, I must tell you that this year the third floor corridor on the right-hand side is out of bounds to everyone who does not wish to die a very painful death."

After the feast, the students followed their Prefects, who monitored the behavior of their respective Houses, to their dorms. Percy, the Prefect for Gryffindor, led them up marble staircase. They moved portraits and doorways hidden behind sliding panels and hanging tapestries. John could only hope that he would remember how to get there. They even ran into Peeves, the castle poltergeist. Finally, they stopped in front of a portrait of a very fat woman in a pink dress. Some of the kids gasped as she began to move.

"Password?" she asked.

"Caput Draconis," Percy told her.

The portrait opened, and they entered the hole in the wall. Once they got inside, the room was cozy and filled with squashy armchairs. John goes with Harry, Ron, Seamus, Dean, and Neville to their dorm. There are six four-poster beds with red, velvet curtains around them. They are all too full and sleepy to talk that they end up changing to going to sleep.