Snape could feel the anger building inside. He had been through so much that night -- elation, despair, pride, shame, hope, fear -- and he had now reached the very limits of tolerance. He needed to learn occlumency! He had to protect himself! Didn't Dumbledore understand that? For Snape, it was either success or death. He noticed that his hands were shaking. His vision blurred. No! He was not going to break down. He was just tired. Dumbledore must have waited until this moment deliberately, hoping to use Snape's weariness to his advantage. A small, horrified voice in Snape's mind suggested that maybe this whole evening had been a trap. Perhaps Dumbledore had tricked Snape into opening his mind. When Snape had revealed enough information about the Dark Lord, the Death Eaters, the events of the last year -- would Dumbledore have him sent to Azkaban? The shaking was becoming obvious -- he folded his arms to control it.
"Why ask me now?" he said, struggling to keep his voice steady.
"Severus, if you are to master occlumency then you must --"
"Yes! Exactly." Snape interrupted, anger over-riding his doubts. "We should be concentrating on occlumency, not wasting time on the whys and wherefores of my life."
Dumbledore stood up, his eyes flashing dangerously. "This is not wasted time! It is essential that you understa --"
"WHY NOW?" Snape shouted, springing from his chair. As if in warning, the curtains billowed gently with the breeze from the open window, and Snape continued in a quieter tone. "Why are you suddenly so desperate for answers? Why?"
"It is not I who needs answers, Severus," said Dumbledore, beginning to pace around the room, frowning Snape into silence. "If you truly wish to master occlumency then you must be in absolute control of your mind."
"I am --" Snape began, but Dumbledore carried on.
"As you are very well aware, tonight I have shared in many of your thoughts, your memories, your fears. When I explored your building, I noticed several corridors filled with dust and cobwebs -- clearly never visited by you. When I roamed through that delightful forest, I could see that the path avoided certain dense thickets -- again clearly never visited by you. As clever as these constructs are, they merely serve to demonstrate that you are hiding your thoughts as much from yourself as from an intruder."
Snape said nothing. He was thinking of how easy it had been to create the building and the forest in his mind, remembering certain corridors with turnings he had ignored, and the way the forest path had seemed to avoid the dangerous areas by chance. What if he were to turn a corner, step off the path? What would he find? What would his master find? What had his master already found?
"Surely the Dark Lord would have already noticed them," said Snape. He was still too agitated to sit down, and was masking this by pretending to study the portraits on the walls. "And if I were to deal with them now, or try to remove them, he would suspect."
"But if you do not deal with them now," Dumbledore replied, "you will never be able to practise occlumency effectively. You must know the contents of your mind absolutely if you are to have any control."
"And then he would know," insisted Snape. Could Dumbledore not see? Once more Snape seemed to be faced with a choice of death or ... death. Wearily, he sat down.
"Please understand that I cannot give you a full explanation. I can only say again that it is imperative that you reach a solution on your own. And so I must ask again -- why did you become a Death Eater?"
In Snape's mind he could see himself walking along a path underneath a dappled green canopy. He forced himself to step off the path, to try to reach the darker interior of the wood, but before he could ...
"Black. Potter," Snape muttered. Why try to hide anything from Dumbledore now? "How could I be on the same side as them? They made it very clear that they considered me the enemy when we were at Hogwarts. Oh yes, their attempt on my life made that very clear. They should have been exp--"
"You are stalling, Severus," said Dumbledore with impatience. "This is not the answer."
"Potter and Black, always together, always cruel. I always knew they were potential murderers," snarled Snape.
"You know very well that James did not know of Sirius's plans that night. He risked his life to save you," snapped Dumbledore in return.
"I could have been killed, and what did you do? Nothing. I trusted you to do the right thing, to punish them. You did nothing." This was a confrontation that had been long delayed. When he had been a student, he had been too much in awe of his headmaster to question his judgment. Now, it was such a relief to be able to finally say this to Dumbledore that Snape felt light-headed.
"On the contrary, I did everything I could. I gave Sirius a second chance," replied Dumbledore, looking directly into Snape's eyes. "I saw someone who had made mistakes, taken unwise decisions, caused others pain through his actions. I saw someone who regretted his past. I wanted to give him the opportunity to make something better of his life. Everyone deserves a second chance, Severus."