Disclaimer: I don't own Harry Potter (duh).

Autumn 1997

Late one evening, while McGonagall was staring out the window in her office in Gryffindor Tower, she noticed a small boat sailing across the lake towards the island that was home to Dumbledore's grave.

Who could that be? she wondered. Could it be the Carrows, going to desecrate the late headmaster's tomb? Could it be some of the students in Dumbledore's Army, going to pay their respects? Either way, she had to follow them.

She grabbed the broomstick leaning against the wall and quietly opened the window. Looking around to make sure no one could see her, she stepped out onto the windowsill and took off. Casting a Concealment Charm around herself, she took off across the grounds and flew over the lake until she reached the island.

The person - or people - in the boat had already arrived. She saw the back of a man's head, a man who stood right next to the white marble. Snape. Her stomach twisted in anger. What was he doing here? Looking around, she saw that he was all alone. She put down her broom and approached him, wand held high.

"Coward," she snarled. Snape raised his head but did not look at her.

"Won't even look me in the eye, will you? I who taught you, I who worked with you for nearly twenty years under him?" She pointed her wand at the coffin, then back at Snape. "I trusted you because I trusted him. He told me that he had a good reason for keeping you on. But then you went and stabbed him in the back, didn't you? All those years of kindness meant nothing to you? And what have you come to do now - rob his tomb? It wasn't enough to take his life, you have to take his dignity as well? ANSWER ME!"

Snape turned around slowly. He did not raise his wand. She could tell that he had been crying.

McGonagall was so shocked she almost dropped her wand. She suddenly felt cruel for having shouted at him. She had never seen Snape like this before, never. It had to be a trick, right? Those tears couldn't be real, could they?

"I made Dumbledore promise," Snape said slowly, "that he would never tell anyone why I worked for him. Now that he's dead, I suppose that promise is moot. If anyone can be trusted with my secret, it is you."

"If you're going to kill me, go ahead and get it over with," McGonagall said defiantly, still raising her wand. "I will not be mocked."

"Lower your wand, Minerva. I am not going to harm you."

"So it's Minerva now, is it? Severus?"

"Yes, Minerva. I am your boss. And you will address me as Professor or Headmaster."

"Over my dead body."

"No," said Snape matter-of-factly, pointing to Dumbledore's coffin. "Over his dead body."

"You swear you will not harm me? On what? On his grave?"

"Yes, Minerva, on his grave."

McGonagall lowered her wand, all the while glowering at Snape.

"You cannot afford to be so reckless with your life, Minerva. The students depend on you."

"Why did you come here?" McGonagall demanded.

"The same reason as you," said Snape. "Don't think I haven't noticed you and Flitwick and Sprout and Hagrid coming over here at night to visit him. And if I notice something, it's only a matter of time before the Carrows do as well."

"Why should I believe you?"

"Do you remember his blackened hand, Minerva? He was dying from a cursed ring. If you need further proof, his portrait in my office has all the information you require."

"He was your friend," said McGonagall, trying to force the hatred back into her voice.

"Yes," said Snape sadly. "He was."

He told her everything. How he had come to Dumbledore on that windy night seventeen years ago and begged him to protect Lily; how Dumbledore had persuaded him to remain at Hogwarts after Lily was killed; how he had protected Harry for Lily's sake; how Dumbledore made him promise to save Draco's soul by killing the headmaster himself; how he was now secretly trying to protect the students from the Carrows and help Harry in any way he could.

When he was finished, McGonagall was in tears. She felt honored that Snape trusted her so much even after what she had just said to him. She sensed that he had desperately needed to tell someone, to confide in someone after Dumbledore died. And she was happy to be that person. She had always respected Snape as a wizard, and despite disagreeing with some of his teaching methods, believed in his good intentions even when few others did. Now she was glad to see that her and Dumbledore's faith in him had not been in vain, and that she and the students still had a powerful ally at Hogwarts.

"I shouldn't have told you that," he said. "It's safer if you don't know."

"No," she said. "I'm glad you told me."

"Did you know, Minerva, that Dumbledore was buried with the Elder Wand?"

"I suppose," she said. It was customary for wizards and witches to be buried with their wands, and she knew that Dumbledore's wand was the Elder Wand.

"It appears that the tomb has already been broken into and the wand has been stolen."

McGonagall gasped. "You-Know-Who? But - he would've told you - "

Snape shook his head. "He does not tell me everything. Like Dumbledore, he dispenses information on a strictly need-to-know basis."

"B-but the wand answers to you," McGonagall said. "You are the one that killed him."

"I think," said Snape slowly, "that he intended for the wand's power to die with him. Since I killed him on his own orders, the wand did not change its allegiance."

"Either way," said McGonagall, "the wand will not answer to You-Know-Who?"

Snape shook his head. "The Dark Lord should know that merely possessing a wand does not make one its master. Nor does ordering the murder of its previous owner."

"But if he thinks he is master of the Elder Wand, what will he do?" She immediately knew the answer to her own question. She gasped. "Kill Harry Potter."

"And how would he do that?" Snape asked. "No one knows where Potter is."

"He'll lure him back to Hogwarts somehow. I know it."

"Perhaps. Perhaps we should let him."

"Severus! Have you lost your mind?!"

"There has to be a final confrontation between Potter and the Dark Lord. It has to happen at Hogwarts. It is Potter's only chance."

McGonagall sighed. "I suppose you're right. But we will do everything we can to make sure he wins."

"Indeed." Snape conjured two full wine glasses and gave one to McGonagall. "To the headmasters of Hogwarts," he said, raising his glass. "Past, present and future."

McGonagall smiled. "I'll drink to that."