Severus Snape is the Half Blood Prince
The door rapped furiously before Draco Malfoy practically leapt into the room irrespective of an answer. "Professor, I've done it! I've done it!"
"Done what?" said Snape, sceptically
"I've found a way to get the Death Eaters into Hogwarts! I've repaired the vanishing cabinet, it works it really works!"
Snape raised an eyebrow "Have you contacted anybody yet?"
"Yes, yes to check it worked," He said virtually bouncing around the room "it leads to Borgin and Burkes, they are gathering the Death Eaters in Knockturn Alley right now.. they told me to expect them in an hour!"
"This is good Draco" he replied coolly, "You are aware of what this means?"
"Of course! Lead the Death Eaters into the castle and fire the Dark Mark above the astronomy tower" Draco held up The Hand of Glory as he spoke.
"Kill Dumbledore, yes I know" Malfoy frowned like he was having his achievements spoiled by criticism. Snape was concerned that the focus had been put in the wrong place.
"For the sake of your family Draco, you must look like you are going to go through with it, even if you falter, I promised your mother that I would do it if you can't, but you have to try. Remember this was your plan - you're in charge and any assistance you get is.. for favour of the Dark Lord. not to protect you. You're a Malfoy, you'll be being watched"
"Who will watch me who isn't going to die?" Malfoy snapped, he was not reprimanded for his lip, it was necessary for him to work up his aggressiveness if he was going to make any attempt at looking like he would follow the Dark Lords instructions.
"Don't be so confident to presume you're not accountable, just because you think you're on your own" Snape said slyly.
Draco huffed like the wind had been blown out of his sails. Snape ignored his umbrage and continued "Where is the vanishing cabinet in Hogwarts?"
"In the room of requirements - hiding"
"Does anyone know you were there?"
"No!" Malfoy said bolshily... "er.. yes" he then said in a small voice. Snape stood up from behind his desk, now concerned.
"Who? Did they see what you were doing?"
"No" Draco said this time with certainty "it was Trelawny, I blasted her out of the room before she even laid her goggle eyes on me" he said nastily.
That loony woman always had a habit of being in the wrong place at the wrong time. So much for her 'inner eye' "Did she see you leave?" Snape said uneasily.
"No, I heard her around the corner chanting to herself" Malfoy sniggered.
"Then you must go back in there and wait for the Death Eaters to arrive before anyone sees you"
"Who's going to care? Nobody in the castle has the faintest clue what is about it hit them"
"Draco" Snape was now impatient with the boys questioning "Just do as I say, you've just blasted a teacher that supposedly has 'second sight'! We don't want an alarm raised before we actually let the Death Eaters in do we! Now go back into the room and be quick about it."
"Yes Sir" Malfoy said bitterly, and skulked off.
Snape allowed himself five minutes before going to alert Dumbledore. When he entered the Headmasters office, Dumbledore was wearing his travelling cloak. The look of immediate alarm filled his face at Snape's presence
"Master I need to speak with you urgently."
"Did you see Harry?" Dumbledore interrupted, most anxiously.
"No" Snape replied slightly quizzically but with an air of nonchalance.
"Good" Dumbledore looked visibly relieved. "I have to meet Harry in the main hallway, can this wait, I only have a few moments"
"Albus" Snape said pressingly "The Death Eaters will be entering the castle tonight, Draco has found a way to let them in"
Dumbledores demeanour remained as calm as it had always been when discussing his forthcoming death, but his expression shows signs of urgency"
"How has this happened.. No I have no time, it doesn't matter, all that matters is that tonight is when I die" Dumbledores remained annoyingly light "Fortunately I have asked members of the order to patrol while I'm away so hopefully it won't be too messy" His tenor sounded like he was making a joke.
Snape watched as Dumbledore busied himself, now knowing this would the last time in his office. He appeared to be running something through his mind. "Look Severus," he said stopping what he was doing for a brief moment "There's something I need to let you know" he sounded ominous "Harry knows about you and the prophecy"
"How?" Then he thought of that woman roaming the corridors "Trelawny!" he said with most distaste. "What did you tell him?"
Dumbledore was miffed how Snape had reached that conclusion so fast "All I have said it what I have always said, that you had utter remorse for your actions"
Snape was deeply irritated; Dumbledore continued to whip around his office putting things in order before the inevitable end. "I'm sorry this has come up right now, but I really have no time to ponder on it, Harry and I have a task to do" He said quite patronisingly.
"Does this mean Potter will be with you later, when you return to the castle?"
"Yes, I expect so, I will protect him for as long as I can - but you must make sure no harm comes to him when it is over"
Snape could feel his irritability burn into rage "This is fantastic" He said, disregarding the fact that Dumbledore really just wanted to get on "So Potter is aware of my part in his parents death, and is about to witness me kill you - but of course I am later expected to convince him to stand before The Dark Lord and sacrifice himself." He said infuriated, his arms folded across his chest "At what point do you think he going to believe me!"
Dumbledore remained calm and to the point but did not stop what he was doing. "You will find a way, you have to.. You could always just tell him the truth"
Snape snorted unreservedly "How did you come to have so much faith Albus?" The sarcasm flew off his tongue as he suppressed himself from yelling at Dumbledore. He was visibly shaking with resentment, all these years, everything he had done and it came to this! Dumbledore couldn't even give him the courteousy of his attention because he didn't want to leave Potter waiting. Without saying another word he turned and walked towards the door.
"Severus!" Dumbledore grabbed his arm, now, finally prepared to engage in a proper conversation.
"How many years have I spoken out about my faith in you? I have unreservedly pledged my trust in you to who ever the doubter. Trust me, like I have trusted you" Snape felt those blue eyes reading his soul, he broke eye contact as if to rebuff what the old man was saying, but Dumbledore wasn't having any of it, he tightened his grip, stopping him from backing away "This thing is bigger than the both of us. This is bigger than Harry Potter. What we do now if for the greater good. You do understand?"
Snape looked back into those warm blue eyes for what felt like the last time. "Yes" He said barely able to speak for the wretchedness within him.
"Then it is time for us to say goodbye my friend" Dumbledore smiled kindly. Then something happened that appeared involuntary and yet instantaneous on both sides. The two men put their arms around each other all but for a few seconds, Snape could feel under the layers of robes, there was hardly any flesh left on those bones.
He pulled away and left the room without looking back and without uttering another word, returning to his office.
He slumped behind his desk feeling drained of all emotion, which was an unnerving prospect for anyone whose job it was to maintain composure. His eye cast upon the large pile of parchment he was halfway through before being interrupted. It was Gryffindor and Slytherin NEWTS homework. Automatically he got out his quill and began to work through the pile. Time would pass slowly and it was something to do to relieve the tediousness of waiting; at least it wasn't 1st year drivel.
After having failed more than half, it seemed such a pointless exercise, a complete waste of time to be spending these last moments - still trying to drag the students up to some kind of level of competency. In a few hours when the school would awake to the horror, nobody would care if they passed or failed their Defence Against the Dark Arts homework, or whether he'd even been bothered to mark it before his departure. For a job he'd spent so many years applying for, he had never felt so much detachment from the subject.
The more he dwelled on the notion the more petulant he became which resulted in him swooping the pile of parchment off his desk. He hit them harder than he realised as three managed to find their way into the fireplace. He quickly got up to retrieve them, but then stood motionless and instead just watched the fire, transfixed as the paper curled and blackened and fell away into ash.
From the back of the room he produced a bottle of spirit and poured generously into a glass, stood by the window and stared into the liquid. In these circumstances a Gryffindor would boast their endless supply of courage and valour, but this did not hold well with a Slytherin. A Slytherin looked towards their resourcefulness and cunning, but how could this be of use with what lay ahead? Courage was found is the obscurest of places. He downed the spirit in one.
From the silence of his office he could hear the sound of heavy footsteps, followed by yells, and then screams. He poured another drink, then promptly changed his mind, sliding the glass across the desk.
The door suddenly burst open and Flitwick staggered into the room sweating and panting. "Severus" he managed to get out in between breaths "Death Eaters are all over Hogwarts.... you need to come with me and help!"
Snape was already armed with his wand, low by his side. He calmly waved it and Flitwick fell to the floor; Stupefied.
This was it, he sped from his office, almost bumping into 'know it all do gooder Potters little friend Granger' and the clueless crackpot Lovegood. He flew instructions as he passed them "Professor Flitwick has collapsed in shock, he needs immediate attention, I need to help fight off the Death Eaters - take care of him"
"Yes Professor" They said in unison and proceeded to fuss the fool on the floor, leaving Snape the opportunity to ascend to the astronomy tower.