Hermione took a quick shower and rummaged around for a decent vintage of wine. If we're going to talk, I'm going to get through that wall a little. The prospect frightened her some, but she knew that his defenses had to come down a little for him to be of use to her in this project. She didn't exactly approve of Dumbledore's all-too-obvious machinations, but she admired the logic she knew was behind this. There is a time and place to reopen old wounds, she admitted to herself. I need his input.

Even if it wasn't the potion that was part of the spell at issue, she knew that his logical eye would see something she might have missed. He certainly had enough command of the other disciplines involved, and the "grey arts" she was incorporating with the Ministry's permission were old familiar territory for a Death Eater.

Checking the time, she realized she had just enough time to pull back her hair and throw on some old jeans and a shirt before Snape was likely to appear in her living room. She was seated on the sofa when he suddenly appeared.

"Professor Snape."

"Miss Granger. Or, should I call you Dr. Granger now?"

"Actually, Hermione would be fine."

Realizing he had never reached that level of familiarity with her name, even though he knew so much about her, he nearly choked on the name. "Hermione, then. And please call me Severus; you haven't been my student for 5 years. So. Let's see your notes, and maybe you can catch me up on your latest incarnation of the spell."

Always one to cut to the chase. "Can I tempt you with some Ogden's? Or a glass of wine?"

Gods, does she know how alluring she can be? An inaudible sigh escaped, as he responded, "If you are having wine, I will take a glass; please don't go to any trouble on my account."

"No trouble; sometimes I find that a little wine can actually bring problems into sharper focus." This made sense, of course, and was a technique he often employed. As long as you didn't fall too deeply into the bottle, sometimes in the relaxation alcohol offered, answers became clear.

Glasses in hand, Hermione brought Severus up to date on the research. "As you undoubtedly are aware, my research involves giving the best properties of a ghost to a mortal for a short time. The ability to be invisible is easy enough," waving her hand artlessly in the air, "but cloaks and charms can't make you non-corporeal. The sticking point has been making the spell attribute the ability to go through walls and keep oneself completely undetected; the rearrangement of atoms…"here her foray into Muggle science was a point in their favor, since atomic theory wasn't something widely discussed in the magical world. "…requires so much effort on the spellcaster's part. That is where I am stuck…granting enough magical power when in noncorporeal form to be able to travel into and out of places at will. Apparating, as you might be aware, leaves too much of a magical trace to be usable. We must have the spellcaster be undetectable by conventional or magical means."

"I was incredibly close," she continued as his eyes raised. "I suspect one of my arithmantic calculations is off, though I won't say that the potion might simply be…flawed. That's where your help would be most gratefully accepted." She took a deep breath, and then sipped her wine expectantly.

Snape pored over her notes, fascinated. She was truly an amazing intellect; the fact that she could combine so many disciplines within magic, and Muggle physics and chemistry, into such an intricate spell was nothing short of phenomenal. Not that he was going to give her the satisfaction of hearing this from him, of course. He knew all too well how Diggory and Dumbledore..and Potter, his mind spat…coddled and encouraged her. Besides, a word from him made no difference. But, the problem with his logic was obvious. Once her spell was perfected, he could retire from his double agent role. Anyone could drift into a Death Eater meeting, listen in, and leave without being detected. Even regular ghosts couldn't do this, because they were tied to buildings and couldn't move between them or go very far from them. Of course, the problem was, if Hermione's work was ever discovered by the forces of the Dark Lord, the war would be lost for the forces of Light. It was reminiscent of the Muggle development of the A-bomb at the end of their World War II – whoever harnessed the destructive power of the atom first would win the war. The stakes were high, and only a very few who were completely trustworthy knew of her research. Everyone else only believed she was a minor functionary in the Department of Misuse of Muggle Artifacts working for Arthur Weasley, and former Auror, hiding from her fame.

For a moment, realizing the stakes involved here, the weight and thrill of having such trust from Dumbledore overwhelmed him. He really was not worthy.

Swallowing some wine, he nodded curtly. "Miss Granger…Hermione. This work is…acceptably thorough, to this point." Her eyebrow cocked at this comment. Anyone who knew Snape knew this was quite a compliment and quite rare. She filed that away for future reference. "It will take me some time to peruse your calculations and work through the charms involved, and of course I'll want to sit down with your other correspondents at Hogwarts." He paused, and dove in where spirits fear to tread, hoping he wasn't making the largest mistake of his life. "I would suggest a sabbatical of sorts for you. Your laboratory was destroyed, correct?" She nodded. "Come to Hogwarts. We can all pore over this together, and I will…" Well, Snape, if you're going to do it, might as well not go halfway. "I will make my private laboratory space available for the research…if you can stand being in the dungeons, Gryffindor." He tried to sneer, but somehow failed.

For a moment, her veneer of hardness dropped. So many memories buried within the walls of Hogwarts, some that she feared and some that, frankly, tantalized her. It would be good to see Albus and work through a few of the things that only he knew about her, that only he could help her with, that she had left unused since her time at Hogwarts. Of course, it would be wonderful to spend time with Minerva and Poppy Pomfrey, and…Severus was right, her lab was a mess. There were far more reasons to go than to stay in her dreary flat while waiting for the lab to be rebuilt, re-warded and hidden.

A wicked glint crept into her eye. "I'm not one for spur of the moment decisions…I have an owl or two to send tomorrow from the ministry." She did not ever owl or receive owls at her London flat, as it would be too risky. "But you can tell Albus that he can expect a scholar-in-residence if he so agrees, and in exchange, I will volunteer to tutor a few students. Have to earn my keep, you know."

"Hermione." An unusual edge crept into his voice…one that she wasn't sure anyone but Albus Dumbledore and herself had ever heard, but she had heard it before, 6 years previous. It was the edge that belied his emotions regarding that night, what she had become, and his perceived role in it. "You have more than earned your keep, and you know that. I will relay your message to Albus. We can expect you tomorrow, then?"

"Yes, Severus. See you for tea? I would like to see the lab, as to be frank, I don't recall ever seeing it in my years at school." An outright spar, and something he felt much more comfortable with than the frankness of the discussion at hand.

"As you wish. In my office." He stood to leave. One could apparate out of Hermione's flat, as Apparation only required that you visualize the place you want to be, and required no knowledge of point of origin. Her flat was Unplottable and certainly non-magical, but that didn't matter when apparating away.

"I will see you there. Thank you again, for your time and effort on behalf of the research."

He nodded, and disappeared with a pop.

She sighed, and shivered with the unusual cool of the weather. It was time for bed, Granger. Time indeed. She changed for bed and sat down to write a few notes that she intended to owl tomorrow when her Muggle telephone rang.

Only one person had that number. "Harry," she answered the phone.

"Hello love. Missed you today, was off in Lancashire chasing a bad tip by one of our favorite informants." He snorted, and she knew he was talking about Pansy Parkinson, whose favors could only be culled with the neverending promise of somehow ending up in Harry's bed.

"Indeed. I'm still not missing the life of an Auror." She cleared her throat and dived in. "Well, the experiment blew itself to kingdom come."

"So I heard from Amos. What's your next move?"

She considered his face if she confessed Snape's visit this evening, and decided to leave that detail out. Harry and Snape really, truly detested one another, and probably for good reason, but she didn't want to go there. "Hogwarts. I need a lab, and a perfect one exists there." Before he could object, she continued, "Besides, all the experts are there, and there won't be as many tired owls if I'm right there for a while."

"Running away from me then, I expect?" She heard the hard edge, and it wasn't unexpected.

"Harry. You know better."

"I know nothing, these days."

She sighed. Their emotionally charged, desperate relationship of 6 years ago had dulled over the intervening months as she realized that they were not truly compatible, but that didn't stop her from letting it go on too long. She had released him, unwillingly, from their engagement nearly 2 years ago, but Harry didn't stop hoping. She kept waiting for him to move on; to meet another woman, to finally put their past behind them. She loved him very much, but she was not in love and never would be. At an intellectual level, he understood this and admitted she was right; but on a purely male hormonal, and in some sense emotional, level, he had a hard time with not being in her bed anymore. They had become excellent lovers to one another, certainly; but it wasn't enough, in the end.

"I'm not running away from you, though I have to admit sometimes you make me want to run away. You can be quite impossible, Harry Potter." She hoped that had the light note that she intended, and at his response, she knew she'd achieved that end.

"I know, I know…sexual frustration, darling, that's all."

"You need a woman."

"Probably. Hey, did you see the Cannons play last week?" His change of topic was welcome to both of them, and they chattered on about Fred and George (his housemates, the Weasley twins), Parvati and Seamus's baby daughter, and other small talk. Then as they were about to hang up, Harry dropped the bomb.

"Hermione…be careful at Hogwarts. I shouldn't tell you this, but what the hell, you're still an Auror, technically."

"Go on."

"We have reason to believe that Snape might be acting under the Imperius Curse these days."

She couldn't have been more stunned if he had announced he had actually slept with Pansy Parkinson. Her Auror senses would have surely picked that up if… "What makes you say that?"

"One of our agents, who is in the same dangerous line of work as the man we're discussing, insists he saw Lucius Malfoy cast a mysterious spell on Snape last week. Just a word of warning. Be careful."

"Hmmm. I guess it's time to come clean, I had Snape to the flat tonight."

She heard the audible choke. "He knows your location?"

"No, I had him use the Portkey. Dumbledore sent him to convince me to go back to Hogwarts."

"Disturbing. Keep your guard up, ok? You know that charm I taught you to discover whether someone is acting under Imperio? Might cast that surreptitiously; or at least, grab a Sneakoscope in Diagon Alley. Think I'll owl Dumbledore, just in case."

"You do that. Harry?"

"Yes?"

"Sweet dreams, love."

"You too, 'Mione."