Interlude: "Unbreakable Vow"

I'm working on the fourth chapter, but it's coming along slower than I would have liked. I wrote this today, and it fit into the background plot I wanted to include at some point. Someone mentioned that the potion Dumbledore drank probably wasn't the one originally there… RAB, who stole the Horcrux, probably drank the first batch and replaced it with the second, more deadly one as a surprise for Voldemort whenever he returned. We talked about how the original potion was one that Voldemort would have to drink, so there must be some kind of antidote for it, which enabled RAB (be he Regulus or not) to survive long enough to escape.

So here's a little something to tide you over for another day or two. Sorry for the delay.

March 1980. Spinner's End.

"You have to help me."

It's said in a tone that begs for aid of any sort. Severus has never heard anything even resembling 'begging' coming from Regulus Black, and knows he probably never will again.

"And why," he sneers, "Do you think that I will help with this... this suicide mission of yours?"

Regulus slumps back in his chair and focuses his eyes on the shelf of books behind Severus' head. The room is small, and lined with shelves, though most are empty. Severus dreams of a day when the house will be filled with books on Dark Arts and Potions, so full that the door to the bedroom itself must become a bookshelf. Someday, perhaps. For now, though, he has other things on his mind.

"What do you want the potion for, Black?" he asks, his tone as cruel and cold as it is when he speaks to the teenager's older brother. Thankfully, at least this one is tolerable.

Regulus is silent. "Do you remember," he says finally, "when we were in school? You were seventh year, I was sixth. It was the night before Halloween, and we were in the common room with that fourth year, whatever her name was?"

Severus doesn't reply. He remembers that night all too well, and knows what Regulus will ask of him.

"You made a Vow to me, Severus. There is an Unbreakable Vow between us. You oblivated that girl, afterwards, sent her on her way, but I still remember even if she doesn't." He takes a moment, breathing deeply. "You swore that you would help me if my life ever depended on it. I vowed to do the same. A bond between the best of friends, and one that cannot be broken."

A sigh fills the tiny front room of Severus' house on Spinner's End. "It is that important that I make you this potion? So important that you hold me to a vow made while we were both still in school, a vow made in during a friendship that did not last after I graduated and we went our separate ways?"

"Yes."

"Fine. I'll make you your potion. This had better be worth it, though."

When Regulus speaks, it is barely heard. "It's worth everything I once thought I believed. It's worth it to save the world from a madman who strives for immortality. If this works, he won't know it was me until it's too late."

Severus doesn't reply, just opens the door and waits for his former friend to leave, then moves to his room to start on the emerald-coloured potion.