Chapter 18

Explosions

If Severus had wanted to assassinate someone, he would have imperiused them to wander onto the path of an oncoming train. If he'd wanted the death to make a statement, he would have transfigured a small portion of his enemy's tea into Polonium-210 before they took a sip. Avery, however, had flashier ideas on the matter.

"So, the first part of the encryption process involves a simple arcanius charm," Lily was saying to James as she demonstrated over the back of a napkin. "Say sepu speu aracnium nox, waving your wand in a figure eight. Make sure you say the words at these points on the figure," Lily drew a figure eight with a pen, and put a dot on each point of the figure where one was to speak, "and then say your password when you hit the center."

"You think this charm is simple? It took Remus ages to get it right, when he tried it."

Severus did not think Avery's plan would work, but he still needed to tell James about it. The problem was, he wasn't sure how to the broach the subject.

"A powerful wizard will be able to break through the arcanius, of course, which is why the actual information will be written in a cipher. I've written the basic integral formulas here, but I've replaced certain parts with arithmancy symbols. As you know, the numbers in arithmancy correspond with letters of the English alphabet, and vice versa. A normal wizard would not be able to tell which parts had been replaced, because they aren't familiar with muggle calculus. A normal muggle won't be able to understand, either, because they don't know arithmancy. But a powerful wizard who had studied muggle sciences…"

"You mean Albus Dumbledore!" James exclaimed.

"Exactly- or certain muggleborn wizards could crack the cipher, as well. However, since you found a secret passage that leads to Dumbledore's liquor cabinet, we can be sure he'll receive the information."

"And even if it falls into the wrong hands before he gets the message, no death eater will be able to read it," James said. "Lily, you're so brilliant! I could kiss you."

"Well, why don't you kiss me, then?"

Severus had been trying to get a word in edgewise all evening, but Lily and James had been so excited about their discoveries that they'd been talking nonstop all morning. Now, however, their lips were otherwise occupied, so Severus took advantage of the opportunity.

"Avery asked me to build him a time bomb."

James and Lily broke their kiss and stared at Severus.

"A… what?" James said slowly.

"Well- the magical equivalent of a time, bomb, I guess," Severus continued. "He wants me to brew a potion that contains all of the force of a powerful reducto, and he plans to transfigure the potion into something innocuous. Regulus will plant the bomb onto Sirius, and then when all of Sirius's friends are together, Avery will release the transfiguration. As soon as he does…"

"Kaboom," James finished grimly.

"The problem is, I don't know what Avery is planning to transfigure the potion into. I hope that, once we warn him, Sirius will be able to catch his brother in the act. In the meantime, I'll have to create a dud potion and then, if it actually goes off, tell Avery that it's practically impossible to create a potion with that much explosive potential- which is true."

"It's possible," Lily said primly. "It's easy for a wizard to create enough liquid oxygen to do the trick- all he'd need is a strong enough frigidiro."

Lily leaned over, scribbling on Severus's notebook. "Liquid oxygen, liquid hydrogen, kerosene…"

"We'd need a catalyst so it would go off on its own," Severus said, leaning over the formula that Lily was sketching out. "Perhaps if we added hellebore-"

"Wait a minute- are you two actually going to build a bomb for this guy?" James exclaimed.

"Oh- ah…" Severus put down his quill.

"Of course not, James. This would make a brilliant rocket fuel, though," Lily said, sighing.

"One day, we'll build it," Severus said gently. "If we don't blow ourselves up, trying. For now, I'll just make a potion that will flash and emit a loud bang without actually causing any damage."

"A wizard flash-bang. That could do the trick," Lily said.

"I'll warn Sirius, in the meantime." James said. "I could try to warn the others but… well, they'll ask how I found out, and none of them know about us- no one but Sirius."

"You are certain that he was ok to trust with this information?" Severus said.

"Definitely. I know you don't trust Sirius, but trust me when I say he would die before he betrayed us."

Severus nodded. "Don't worry about the others- the potion will be completely harmless if it does go off, but it will be best if it looks like Sirius caught Regulus all on his own. That way, I won't have to explain the dud potion."

James nodded, and then he stretched and yawned. "I have quidditch practice this afternoon, so we should probably get some occlumency practice in now."

"Alright," Lily said, putting her notebook away. "How do we start?"

"Just clear your mind, and try to keep it clear while I cast legilimens," James said. "If you stay focused, you'll be able to feel my attack and block me."

#

Later that afternoon, Severus walked the halls aimlessly – lost in thought.

He was exhausted, yet exhilarated from his first experience with mind-magic. He had only tried occlumency so far, but he'd found he had a natural affinity for it. On his first attempt, he was not only able to detect James's intrusion, but for a few moments he'd actually held James at bay. Then, on his third attempt, he'd let James in and effortlessly diverted him toward a false memory he imagined on the spot. For a minute, James had been fooled into thinking that Severus and Lily had once hijacked a zeppelin.

Severus, it seemed, had been designed by nature to be a spy.

Lily, on the other hand, had shown no such affinity for the subject. She was, after all, a girl who openly told her friends when she planned to trick them. During practice, James had inadvertently seen a particularly painful memory of a fight Lily had with her sister, and Severus and James had spent the rest of their time together holding her as she cried.

However, Lily was a Gryffindor through and through, and an initial setback wasn't enough to deter her from her chosen path. Come noon, Lily had wiped her eyes, declared that she was going to meditate a half-hour every day, and then, smiling, changed the subject to the Astronomy club's plans to build a telescope.

As he walked, Severus tried to think of a way to make things easier for Lily, but so far he'd had no ideas. It seemed that Lily would simply have to practice focusing her mind the hard way.

Severus's reverie was interrupted when someone took him by the hand and yanked him into a large broom closet, slamming the door behind him. Severus spun around, but though the closet was well lit, he could not see the culprit anywhere.

Severus spun back and tried the door, and found that it was locked.

"Shhhh- don't rattle the door," James's voice whispered. "Someone will hear."

"J- James?" Severus said, spinning back to the empty closet. "What in the world-"

The air in front of Severus shimmered, and then James stood in front of him, where no James had stood before.

"I have an invisibility cloak," James said.

"Where did you get…"

"Another family secret."

James broke out into a wide grin, and Severus noticed that he had two dimples by the corner of his mouth. Severus reached out to brush them with his fingertips, and then he pulled James closer, kissing him deeply as he ran his fingers through that messy tangle of hair.

"You infuriating," Severus gulped as he came up for air, "incorrigible…"

"You forgot sexy," James said.

Severus pressed another kiss against James's lips, and then pulled away. "This is reckless. We'll get caught."

"We'll be fine. I locked the door, and no one was around when I got here- I checked. When you leave, I'll put on my cloak, wait five minutes, and go."

Severus nodded, and then kissed James again.

"God- I hate to say this," James groaned, "but I didn't bring you here just to make out."

"My apologies," Severus said, pulling away.

"No- don't do that," James pulled Severus back into his embrace. "We can talk just as easily like this."

Severus chuckled, leaning his head against James's chest. "So- talk."

"I was just thinking; when Avery's plan fails, he's not going to give up. He's going to try again, and he's going to pressure you into helping him again."

"Yes- you're probably right," Severus said.

"I have a plan- one that will provide you with a very good excuse not to come after me any more."