The train gave a whistle and departed Platform 9 and 3/4. John Watson sat in one of the few empty compartments in the train, reviewing his lesson plans for the first week of school. He reread and muttered things to himself, occasionally taking a quill and editing something.

Another person entered the compartment, making John look up. He was greeted by a tall man with dark curly hair and striking colorful eyes. The other man said nothing and simply sat down across from Watson, but not in the usual way. He lay down on the bench with his feet up and his hands pressed together under his chin.

"Hello," said John.

No answer from the new passenger.

"I said hello." Watson was slightly louder this time.

The mysterious man turned his head and looked at John as if noticing him for the first time. "Afternoon," he said, then resumed his previous position.

"Might I ask who you are?"

The man sighed and sat up, as if realizing and dreading he would actually have to converse. "The name is Sherlock Holmes." Sherlock extended a hand.

"Professor John Watson." He grabbed the hand and firmly shook it.

"I'm curious," said Sherlock. "How many years did you serve as an Auror before turning to teaching?"

"Seven. Wait-"

"And what drew you to Defense Against the Dark Arts when you have a natural knack for Transfiguration?"

John took a second to turn that over in his head, make sure he heard it right. "Pardon?"

"Well I can see your lesson plans to start, which gave away the subject you teach. The Transfiguration bit I figured out through your wand. Around 10 1/2 inches typically indicates a strength in that field. The fact that you were an Auror is evident in your posture and hair, prematurely growing gray and proud posture. This is an indicator of extreme duress, and I noticed a small scar on your hand, no doubt from something slightly dangerous at least. That's not all though, you felt the need to introduce yourself immediately. Most people would've ignored the random man who came into their car, but as an Auror, it would be in your nature to not only be curious, but to glean some information from this stranger." Sherlock sat back in his seat, clearly pleased with himself.

Professor Watson blinked. "You figured all of that out from a single look?"

"Among other things."

"Interesting. Well, you know me now, but I haven't the faintest idea about you. What do you teach?"

"I'm the new Potions Master this year." Unless he was explaining his insane ideas, Sherlock seemed to like to keep things short.

"And what did you do before that?"

"I had a job in the Weasley Dragon Reserve in Romania."

"And you've decided to come to Hogwarts why?" Dragons to Potions Master was a pretty enormous job change.

"I got bored," Sherlock replied and shrugged as if that were perfectly normal.

This man was ludicrous. John sat forward, elbows on his thighs. "Bored? By dragons?"

Sherlock leaned in, "It wasn't really so much that I was bored, more that Mr. Weasley was sick of my-"

"Candy trolley!" interrupted a voice. Mrs. Hudson, the school nurse who liked to help out wherever she could, leaned into their little compartment. The boys immediately sat up straight.

"None for me, thanks," asserted John.

"Some Bertie Bott's Every Flavor Beans," said Sherlock, pulling out 5 knuts and handing them to the older lady. "Please."

Mrs. Hudson accepted the coins and dug around in her cart. She drew out a small purple box and handed it to Sherlock. "There you go, dear," she said sweetly. Then she smiled and continued down the isle.

Sherlock opened the box and poured the contents into his hand. He looked at them all, shifting some out of the way to view others, then picked one out and proceeded dump the rest in his mouth. After chewing and swallowing, he held up the rejected bean. "Liver," he announced proudly.

John laughed. "I don't believe you."

"Care to test that?" Sherlock extended an open hand to John, the bean sitting in the middle like it was something of huge importance.

John plucked the candy from Sherlock's hand and made a show of dropping it in his mouth. He began to chew and quickly discovered the taste. It was liver. He wouldn't let Sherlock know though, and did not speak nor make an expression until he swallowed. "That wasn't so bad. Chocolate."

"Lie."

"Pardon?"

"You're lying. I can tell."

John sighed. "Of course you can. That was bloody disgusting."

Sherlock laughed smugly, a light and low-pitched laugh that for some reason coerced John into laughing too. It was cut off quickly by the whistle indicating that the train was about to arrive at the school. John glanced down at his clothes, a ratty old sweater and khaki pants. He stood up. "I suppose I ought to go change. See you in the Great Hall, Mr. Holmes."