As the night grew darker, Kreacher brought Alexandra and Regulus to the same cave the Dark Lord had taken him. The dark sea before them heaved thunderously and crashed to the sharp rocks with loud roars.

"Here, Master," said Kreacher, his voice echoing through the dark cave. Alexandra and Regulus had both drawn out her wands, lightening up the space around them.

Regulus had been thinking about their plan for long hours, and despite how he kept trying to reassure Alexandra that things were going to work out, there was still this feeling in his gut that told him something was going to go wrong.

     What Alexandra didn't know, was the effects that the Emerald Potion had on people. Regulus was ready to drink it, but he also knew that if he did, there was little chance of survival. But if it came to his life and Alexandra's, he would rather die to save her.

     Although knowing Alexandra, he knew that she would try to put his life before hers, and he couldn't have that.

      "Listen, Kreacher," Regulus started as they stood at the entrance of the cave, turning to face the house elf, "The moment you hear the word 'Raven', it means that one of us is in danger. So what I want you to do is to take the person who still has hope for being saved out of the cave."

And that person would be her, he thought to himself. It has to be.

After Kreacher bowed deeply in understanding, the elf helped them pass through the cave's entrance, the same way that the Dark Lord had opened it up.

An eerie sight met their eyes. They were standing on the edge of a great black lake, so vast that they could not make out the distant banks, in a cavern so high that the ceiling too was out of sight.

A misty greenish light shone far away in what looked like the middle of the lake; it was reflected in the completely still water below. The greenish glow and the light from the two wands were the only things that broke the otherwise velvety blackness.

      Regulus and Alexandra stood beside each other, facing the dark lake. The darkness surrounding the cave was somehow denser than normal. Regulus then glanced sideways at Alexandra, seeing that she was lightly shivering, a look of worry in her eyes.

      "Are you scared?" he whispered, looking back at the lake.

     Alexandra nodded weakly. "A little."

     Regulus then smiled at her, holding her hand in his and squeezing it reassuringly as he said with a grin, "Me too."

     For some reason, at those words Alexandra felt lightly better, though she could feel how cold his hand had gotten.

"The basin is there," said Kreacher, pointing a shaky finger at the middle of the lake.

"How do we get there?" Alexandra questioned, looking around as she tried to come up with an idea, seeing as there was no boat in sight.

But before either of them could say anything else, Kreacher had raised his hand, as if reaching out for something invisible in mid-air. The next moment, both Alexandra and Regulus jumped when a long chain shot out of the lake and landed in Kreacher's hands.

"It's the boat," Regulus observed as they all went forward to help pull it out of the dark water.

With an unsure glance at each other, Alexandra and Regulus got inside the small boat along with Kreacher, which started to float across the lake magically.

There was no sound other than the silken rustle of the boat's prow cleaving the water; it moved without their help, as though an invisible rope was pulling it onward toward the light in the center. Soon they could no longer see the walls of the cavern.

Sure enough, the greenish light seemed to be growing larger at last, and within minutes, the boat had come to a halt, bumping gently into something that they could not see at first, but when Regulus raised his illuminated wand he saw that they had reached a small island of smooth rock in the center of the lake.

On the island there was an expanse of flat dark stone on which stood nothing but the source of that greenish light, which looked much brighter when viewed close to.

Alexandra and Regulus moved forward, holding their breaths as they peered into the basin, which was filled with a dark green potion and at the bottom of it the locket of Salazar Slytherin laid.

"Can we — can we get to the locket without actually having to drink the potion?" Alexandra questioned hopelessly.

"No." Regulus shook his head, his eyes still fixed on the locket inside the basin. "All of it has to be drunk. That's how the Emerald Potion works. It creates an invisible barrier which you can only cross by drinking it."

None of them made a move as the silence ruled over the walls of the cave. Then, Regulus dug into his coat's inner pocket and handed a large vial of Emerald Potion he had bought from Borgin and Burkes to Alexandra, along with the fake locket which contained their letter inside it.

"After I've drunk this, switch the lockets and pour the potion back inside the basin."

"Regulus, you can't —"

But before she could protest any further, Regulus had conjured a crystal goblet out of thin air with his wand and had filled it up with the potion, drinking it quickly before Alexandra could stop him.

Alexandra let out a gasp and the next moment, she watched in horror as Regulus's face went pale and his whole body started trembling, falling to the ground and his wand falling out of his hand and away from him.

"Regulus!" Alexandra lounged forward, trying to help him up, but he couldn't.

"Kreacher — keep — me — going!" Regulus ordered with the last bit of strength he had in him. "Don't — stop!"

Against his own will, the house elf picked up the crystal goblet and refilled it, bringing it back to where Regulus laid on the cold ground, writhing. With each sip that he took, Regulus grew weaker and his body became colder.

"Reggie..." Alexandra kept whimpering, holding him in her arm, but it was as if Regulus could no longer recognized her as he shed tears in pain, begging them to stop. It was as if he were seeing things in his mind that the others couldn't, looking like he was being tortured as he yelled.

"Kreacher! Please! Stop this!" Alexandra begged desperately, crying miserably, but the house elf couldn't stop himself. He was was ordered to do as Regulus asked, and not to take orders from anybody else.

Regulus could no longer speak as he breathed heavily for air, which wasn't reaching his lungs anymore. Kreacher was sobbing louder and louder with each time that he went to refill the goblet, feeling agony for hurting Regulus, and yet he couldn't stop feeding him the potion.

But as Regulus drank the last sip of potion from the basin, the pain suddenly seemed to have stopped. He kept mumbling something under his breath, but Alexandra couldn't understand him. She assumed that from what Kreacher had told them, Regulus needed was water.

So quickly getting to her feet, Alexandra exchanged the lockets and filled the basin again with the potion Regulus had given her. She then briskly got hold of the crystal goblet and tried to conjure some water into it, but to her horror the water disappeared the moment it touched the goblet.

Alexandra was still crying as she looked around, until her eyes caught sight of the cold lake, deciding to collect the water from there.

So taking one last deep breath, Alexandra handed the original locket to Kreacher and hesitantly walked toward the edge of the lake, bending down to fill up the goblet with her heart pounding in her chest.

But the moment she touched the surface of the water, she screamed when a slimy white hand gripped her wrist, and the creature to whom it belonged started pulling her, slowly, through the dark water.

The surface of the lake was no longer mirror-smooth; it was churning, and everywhere she looked, white heads and hands were emerging from the dark water, men and women and children with sunken, sightless eyes were moving toward the rock; it was an army of the dead rising from the black water.

She tried to fight them off as she screamed, but the hands kept pulling her down. Kreacher wanted to move forward and help her, but each time, he had to hit himself in punishment, remembering that Regulus had ordered him not to do anything without his command.

"REGULUS!" Alexandra screamed as hands grabbed onto her ankles, starting to drag her through the surface of the water.

Alexandra held on tight to the edge of the rock as the Inferi tried to pull her down into the water. But she held on for her life, tears rolling down her cheeks, screaming Regulus's name for help. She tried to kick the dead bodies with her legs from under the water, but it was helpless.

"No..." This was all Regulus could mutter, but not even that was audible enough. He tried to call out Kreacher and order him to help her, but he couldn't form the words. His throat was too sore to make out a word.

With all that he had left in him, Regulus tried to crawl on the ground, dragging himself forward with the force of his elbows.

Alexandra was still fighting. The dead bodies had grabbed a hold on her with their cold and lifeless hands, trying to drag her down.

"R-Regulus!" she whimpered, the palm of her hands starting to bleed from holding onto the rock so hard.

She couldn't hold on much longer.

Regulus had almost reached her. He wanted to tell her to keep fighting. He wanted to tell her that everything was going to be all right. But he couldn't get the words out.

He just stretched out his hand for her to take, his eyes fixed on hers, both filled with tears.

Panting, Alexandra let go of one of her hands and with great effort she raised it to take Regulus's. Their finger tips were nearly touching.

"Hold... on..." Regulus managed to whisper with everything he had left in him, though it wasn't even audible to her.

But his heart sank when he saw the glimmer of hope vanish from Alexandra's eyes.

Regulus shook his head at her, knowing what she was thinking. Knowing that she was going to stop fighting. Knowing that she was going to let go.

But Alexandra only smiled, a single teardrop running down her cheek as she looked deep into his grey eyes one last last time, before saying loudly,

"Raven!"

     And with that, she let her hand go.

"NO!" Regulus shouted as Alexandra vanished into the dark lake, but before he could do anything, Kreacher grabbed the locket and held onto Regulus's arm, Disapparating out of the cave.