The Internal Devices

Chapter 17

With exams over, Hermione practically lived in their tiny lab at the back of the infirmary. Ginny tried to drag her out every once in a while for a bite of food and a breath of fresh air, but Hermione often slipped away to keep working. Currently, she was sprawled across an empty table, wand waving furiously at the ceiling. A map of color hovered above her, and she fought to keep it steady as Draco sent sparks flying at it, rearranging some pieces, vanishing others, and tweaking the rest. It was tedious work, and both students were sweating profusely.

Theo had offered to come have a look at it, as his spellwork was often more exact than either of theirs, but Hermione didn't want him to have to cancel his Hogsmeade plans with Blaise. Theo had looked so healthy lately that she didn't want him to miss a chance to do something fun if his health declined again. No, she would not take this day from him. So here they were, trying to develop a spell for the fifth time and growing increasingly frustrated.

The theory was quite simple: develop a magical equivalent to a muggle antibiotic. Hermione explained she wanted it to look like an antibiotic and behave like an antibiotic would, just instead of targeting bacteria, it would target foreign magical signatures in the body. Draco agreed, and they chose their positions.

Now they had to choose a spell. Hermione remembered Draco's genius idea a few weeks back to modify a locating spell to get the assay to work, and she suggested they try something like that. They went back and forth for a while but eventually settled on avenseguim, which can turn an ordinary object into a sort of tracking device. Draco would do the modification, while she held the sample steady and cast the spell. After all, they did want to locate something. They initially cast an avenseguim on a mutated mycobacterium from Theo's sample; the hope was to modify it to track other things that were similar. Perhaps it was a long shot, but it was all they had.

For the first hour, the two were all smiles and laughter, even when their first attempt exploded overhead, showering them in a lavender goo. By the fourth attempt, they were frustrated, and now on the fifth, they were exhausted.

"Maybe the locator spell isn't enough? Because we really need to develop something that not only finds the mutated bacteria but destroys them," Hermione gasped out. Her raised arm ached from use.

Draco dropped his wand and sat heavily on the edge of the table Hermione lay on. She lowered her wand as well, relishing the relief flowing through her tired muscles. Draco rubbed his thumb over his bottom lip in consideration. "I think you might be right," he mused. "Hey...can you tell me about the final battle, when Potter fought Voldemort?"

Hermione looked at him curiously. "Why?"

He shrugged. "I have this nagging feeling that something there is important. The problem is I missed a lot of that final hour, but I assume you know all the details?"

Hermione sighed and bobbed her frizzy head. "Well...it was quite interesting, really. So many things about those hours were unexpected, from tracking down the last horcruxes and destroying them, to Harry dying and coming back to life, and especially that duel that changed everything just because of the wand."

Draco gaped at her, mouth widened in an 'o'. She chuckled. "Sorry, I realize you probably have no idea what I'm talking about."

"What's a horcrux?"

She shivered. "Now isn't the time. That isn't going to be what helps us figure this out, I assure you."

"But Granger–" Draco sputtered.

"No, Malfoy," she cut in sternly. When she saw his expression smooth into a practiced cold, grey slipping over his irises, she softened. "Sorry, Draco. It's just that...a horcrux is the darkest evil a witch or wizard can create. It's a form of dark magic that allows one to store a piece of their soul in an object when they commit a murder. This soul-holder, the horcrux, is a way to keep the wizard immortal. As long as the horcrux exists, that person is unkillable."