Over the next few days, Jon Hart kept mulling over his plan.
How could he get a strand of Snape's hair, or a piece of tissue from his body?
But every idea he came up with was quickly ruled out—they were all far too risky...
Snape was an exceptionally skilled Potions Master. His understanding of Polyjuice Potion probably ran even deeper than Jon had imagined.
Stealing part of his body?
Technically possible... but even the slightest slip would likely get him caught. Snape would figure it out, and then deduce the use of Polyjuice Potion. And considering his relationship with Dumbledore, Jon would probably find himself having a "heart-to-heart" in the Headmaster's office within the hour.
That would be the definition of shooting himself in the foot.
One by one, Jon dismissed every idea.
But it wasn't entirely hopeless.
After careful thought, there was still one viable approach... just a little more complicated.
But it was also the safest.
Without further hesitation, he pulled out a pen and some parchment and wrote a letter.
The letter was addressed to Mr. Robert Wilson, the owner of the hardware store at 21 Winchester Road, Southampton. Writing under the alias Varian Urien, Jon asked Mr. Wilson to purchase some specific items for him.
He requested the items be sent to Mr. Hart, Hufflepuff House, Hogwarts School of Witchcraft and Wizardry.
...
About a week later, owls began arriving in the Great Hall every few days, carrying large crates, which they dropped in front of Jon.
"Who's sending you all this stuff?" Zacharias asked curiously.
"Just a few gadgets for Muggles..." Jon replied vaguely. "A relative sent them to me!"
Every time he received a package, Jon would find an excuse to rush up to the Room of Requirement on the eighth floor of the castle and install the contents.
Meanwhile, he waited for the right moment to get close to Snape.
...
Late January 1993, during a Potions class.
Snape spent the afternoon teaching them how to brew a potion called the Sleeping Draught.
Jon and Astoria finished first, and as usual, Snape took his time before checking their cauldron. To prevent the potion from evaporating, he deliberately covered their cauldron with a lid.
As always, Snape took his time criticizing nearly every student in class.
When class was almost over, he finally turned his attention to Jon and Astoria in the front row.
He strode over, reached out, and lifted the lid.
After glancing at the clear blue liquid inside the cauldron, he gave a small nod.
After more than half a semester of Potions lessons, Jon and Astoria had barely made any mistakes, and Snape had grown used to their consistency.
Without saying anything, he reached to cover the cauldron again—
"Professor, let me do it!" Jon said quickly, reaching out as well.
Just then, the scraper in his hand lightly grazed the back of Snape's hand.
"I'm so sorry, Professor..." Jon stood up in a panic.
Snape pulled his hand back with a cold expression. The scrape was barely a touch—no blood, just a faint white mark.
"Sit down!" Snape shot him a frosty look. "Mr. Hart, didn't I already tell you that all blades must be put away after potion brewing?"
"I'm really sorry... I forgot..." Jon quickly sat down and explained.
"Hufflepuff, minus five points."
"Class dismissed."
...
"What were you thinking just now... I can't believe Professor Snape only took five points... I thought you'd be in detention for sure..." As soon as Snape left the classroom, Astoria came over, whispering with a worried look.
"Sorry, I was a bit distracted," Jon replied with a bitter smile, carefully placing the scraper into a crystal vial filled with red liquid.
"Want to head to the Great Hall together?" Astoria asked softly after glancing around.
"No, I've got something to take care of!" Jon packed his things in a hurry and rushed up to the eighth floor of the castle.
...
On the eighth floor of Hogwarts, across from the tapestry of trolls clubbing Barnabas the Barmy—
"I need a cold storage room... I need a cold storage room..." Jon silently repeated in his head as he walked past the wall where the Room of Requirement appeared.
After the third pass, a brass handle emerged from the wall, and he pushed the door open quickly.
The Room of Requirement was now filled with ice. Several crates of rum were tucked among the ice, a clear sign that he wasn't the only one using the space.
Jon shivered from the cold, then hurried to the left side of the room. He moved aside a large block of ice and pulled out several bottles and jars hidden beneath it:
DMEM cell culture medium
Gibco fetal bovine serum
PBS buffer solution
Kanamycin
Ampicillin...
These were all reagents Jon had asked Mr. Wilson to discreetly order for him.
One by one, he unpacked the biological reagents, along with a fresh box of ice.
Since stealing part of Snape's body directly was too risky and difficult, he had no choice but to fall back on his original specialty—cultivating Snape's cells into tissue using lab methods.
As he laid out the reagents, the Room of Requirement began to transform drastically.
The ice slowly vanished, and the room turned into a greenhouse, kept at around 37 degrees Celsius—the ideal temperature for cell growth.
Some equipment began to appear—items Jon had ordered days ago and secretly brought in.
There was a microscope, a centrifuge, and an incubator... After several days of effort, Jon had turned the place into a rudimentary microbiology lab.
He had even smuggled in a small diesel generator to power the more delicate equipment.
Carefully, Jon retrieved the epithelial cells he had scraped from Snape's hand earlier with the scraper.
Immediately after collecting them, he'd placed them into the culture medium—the red liquid in the crystal vial.
Now, he centrifuged the solution at 800g to remove the supernatant, then added fresh medium and serum to the cells.
Since he couldn't guarantee sterile conditions, Jon added antibiotics at a 0.1% concentration to prevent contamination.
After a round of basic treatment...
Finally, Jon carefully placed the cell culture flask into the incubator.
Leaving the Room of Requirement, all he could do was hope—hope that everything would go smoothly.