Severus spent a long time pondering why the Death Eaters might choose to tip their hand by making a move against Hogwarts. It made little sense from a military point of view; the staff were indeed all at the top end of their respective fields, but there were others in the Ministry who were their equals, and better trained for battle.
The only target worth taking down was Dumbledore himself, and Voldemort would have to be a bigger fool than Sev knew him to be to try and attack him here at Hogwarts. Even should the Death Eaters manage to get him isolated and defenceless, their chances of overcoming him were minuscule; to launch an offensive against him in the magical building whose secrets he'd been learning for half a century was literal suicide.
If Voldemort had any brains - and Sev was certain he did - then he would stage the raid when Dumbledore was away from the school. The Death Eaters couldn't help to hold the building, and it wasn't a smart way to go after specific enemies.
That meant that the point of the raid was not practical gain at all, but rather psychological. They had already put the terror into the hearts of many students and parents by demonstrating that they could cause chaos by stealth; prove that they could succeed in a full-frontal assault, and all hell would break loose.
If fears for student safety caused a mass exodus from Hogwarts, the effects would be far-reaching and catastrophic. There were only three wizarding academies still operating in Europe, and Durmstrang was already in the hands of the Death Eaters. Beauxbatons was the newest of the three schools, and if Hogwarts could be penetrated then it didn't have a prayer.
Shatter the wizarding academies, and the Death Eaters already had their greatest wish; the prevention of Muggle-born wizards from ever realising their powers. Without the schools to screen for potential wizards, the 'mudbloods' would never even discover what they were.
Sev doubted that even the most successful raid would accomplish all that. Even so, it would be a huge exercise in intimidation, and that was an end in itself. If Sev's meeting with the Death Eater leader had shown him one thing, it was that Voldemort knew all about the value of causing fear. In some ways, it was like Sev's own strategy in convincing the school he followed Malfoy; blurring the line between what he had been seen to do and what people believed him capable of.
Let the Death Eaters take the advantage this early in the game, and the war might be as good as won. On the other hand, preventing the raid was a bad idea. To do so would be as good as telling Voldemort to his face that one of his information-gatherers was a spy.
No, it would be far better to let it go ahead - and be successfully repulsed. Voldemort would have no reason to suspect his plans had been anticipated, and faith in Hogwarts would be if anything renewed.
So the question became how to achieve that. The obvious solution would be to give a warning - but the only safe person to send it to was Dumbledore, and there was no way to do that anonymously. He preferred to keep that particular avenue for a much more desperate last resort.
Dumbledore was both discreet and fully trustworthy, but when a secret became shared between two people it didn't matter who they were. The only fully secure way to keep a secret was to share it with nobody.
Sev had already broken that rule twice, but Josh was well removed from the thick of things, and he could avoid Lily as long as he needed to. It wouldn't be near so simple to duck the Hogwarts headmaster if he wanted to talk.
He would handle this, as was his fashion, alone in the dark.
Right at the moment, that description was quite literal; he had suggested that the three of them split up and stagger their returns to Hogwarts, with him coming in last. Ostensibly this was to reduce the risk of being noticed, but in truth he had just wanted the solitude. Tightened security had made it difficult to take the late-night strolls he was inclined towards, and he was glad of the opportunity.
However, back at Hogwarts it was much easier to tell whether or not you were the only one creeping about in the middle of the night. There would be much more advance warning if you were about to, for instance, turn a corner and run straight into James Potter.
"Snape!"
James reared back in surprise. Though Sev hadn't expected to see him, he wouldn't quite say he was 'surprised'. It wasn't the shock of shocks to find out James Potter didn't always stay tucked up in bed like a good little boy.
"Potter," he said calmly. "Where are all your little friends? They wouldn't let you go out in the dark by yourself, would they?"
With rather impeccable timing, Sirius, Pete and Remus suddenly emerged from a side street and pulled up short at the sight of him. Snape offered James a thin and mocking smile.
"What the hell are you doing out here, Snape?" he demanded hotly. Sev had learned quickly that borrowing from Malfoy's smug superiority was an excellent way to rub James up the wrong way.
"The little snake - he's spying on us!" It didn't take anything so complex to set off Sirius Black. 'Loitering whilst being in house Slytherin' was generally enough of an offence.
"Yes, Black, I live for the vicarious thrill of your lives," he said dryly. "I don't know what I'd do with myself if I didn't have the excitement of following you four around."
Sirius looked just about ready to explode. James was affecting to be unimpressed, whilst behind him Peter spoiled the effect by jittering nervously up and down. Remus, hanging back as he usually did during conflicts, looked suspiciously like he was trying not to smirk.
"Oh come on, man, you followed us," said James, rolling his eyes. "What the hell else would you be doing out here?"
Sev decided to chance his arm with a cutting remark.
"Maybe I'm trying to find out what haunts the Shrieking Shack." He locked eyes pointedly with Lupin as he said it. The mousy-haired boy did a credible job of keeping an impassive face, but Sev could read it anyway.
"You're out of your league here, Snape," James said warningly, stepping forwards to invade his personal space. As an intimidation tactic, it didn't work awfully well, because he was actually about half an inch the shorter of the two, and Sev was much better at holding someone's gaze without blinking. "You should toddle off home back to bed before you get hurt."
"By you?" Snape made his point succinctly with a snort of amusement.
"By all of us," said Black darkly, stepping in to join his friend. Sirius was taller, quite a way so, but Snape simply gave him an obnoxious smile and then ignored him.
"You should keep your pet here under better control, Potter," he said to James. "Big dumb animals that play with snakes usually live to regret it."
"You should keep your mouth under control, Snape," suggested Sirius, pushing him backwards.
"I quite agree," he said, stepping back calmly and making a show of wiping the front of his robes. "After all, I wouldn't want to end up with a case of that spitting thing you're doing there."
That was enough to snap him, and he lunged forwards - magic forgotten in favour of a good old-fashioned brawl - but James pulled him back. "Leave it, Sirius," he said, although it came out more a command than a suggestion. "Much as I'd like to see him wake up the hospital wing tomorrow morning, he's not worth the hassle we'd get for being out at night. Right now, it's just his word against ours."
"Yes, Potter, I really would turn myself in just to get you four idiots in trouble." Sev shook his head in over-acted disbelief. "You seem to be harbouring the delusion that you actually matter somewhat to me; I'd suggest you lose it." He smiled sardonically. "It may shock you to hear this, but the fact that you get dizzy if you think too fast isn't proof that the universe revolves around you."
Slytherin tradition of getting the last line satisfied, he turned on his heel and walked away.
It was only thanks to his light-footed nature that Sev became aware of the very quiet scuffling behind him as he made his way back to the secret passage. Someone was following him, and with far too little ruckus for it to be one of the Gryffindor boys he'd just left behind.
He didn't look over his shoulder, or try to catch them out by stopping suddenly; such methods were far more likely to alert the follower than give much chance of catching them. Besides, if it was who he suspected it was, looking back would do him little good.
Instead, he waited until he had ducked into the Hogsmeade end of the secret passage. He closed the door behind him, and rather than going onwards simply leaned against the wall in the shadows and waited.
Sure enough, a respectable lead-time later, the secret door opened... and then closed. It appeared to do so by itself, but Snape wasn't fooled.
"You may as well show yourself," he suggested to the empty air. "I know you're there."
"Of course you do." With a rustle of cloth, Lily emerged from under the invisibility cloak. She cracked a sarcastic smile. "You are the great Severus Snape, and you know everything."
"Indeed I do," he nodded, "although the workings of your brain are a mystery for greater minds than mine, should they exist."
"Oh, surely not," she mocked gently, and Sev shrugged.
"Any particular reason you're here, or do you do this for fun?"
She waved the bunched-up cloak at him. "You can't give somebody a gift, and not expect them to use it."
"Do you often follow your boyfriend and his friends when they sneak out in the middle of the night?"
"Firstly, he's not my boyfriend. And secondly, only when they develop testosterone problems and get this idea that only boys can sneak out at night."
"So you follow them and see what they're up to?" He raised a fine eyebrow. "I imagine that's a thrilling occupation."
"It just got more interesting," she countered. "Care to explain what you're doing out here? Unlike James and Sirius, I know you've got better things to do with your time than follow them around to cause trouble."
"Apart from anything else, that implies that Sirius Black and James Potter require outside intervention to be in trouble."
"Nice dodge. Try again, with answers to the question," she suggested pointedly.
"Unlike your little friends, I'm out here on business," he told her.
"Malfoy's business?" she guessed. He inclined his head in a slight nod.
"His... amongst others."
"So you're on the in, then?" Lily said. "These... Death Eaters... have taken you in?" Obviously, she'd heard the rumours that were flying about.
"I think you'll find that I've taken them in," he corrected.
"Modest, aren't we?" she observed. That didn't merit a reply. "No, but I've been thinking," she continued a moment later.
"Oh, dear God," interjected Snape.
"-Quiet. I've been thinking. All these things that have happened on school grounds... they've got somebody, haven't they? Somebody on the inside. There are Death Eaters at Hogwarts."
"More of them than you think." Sev stepped forwards, and pulled back his sleeve to show her the Dark Mark. She gave an involuntary gasp, and looked up at him with worry in her dark green eyes.
"Sev..." she said haltingly. "Are you... are you totally sure you know what you're doing?"
He shrugged, lightly. "I always do," he reminded her. "More to the point, I'm the only one that does, aside from you and Joshua Matthews. He's not here, and you're not stupid. None of us three is going to be giving me away."
Lily looked like she wanted to argue, but she bit her lower lip and said nothing. After a moment of silence, she said "Who is it, then? The Death Eater. The main one, the senior guy. Not Malfoy and his gang of rent-a-thugs."
"I don't know."
She blinked. "That's a first."
"I have my suspicions," he elaborated.
"You always have your suspicions. Nobody's safe from you; I'll bet even Dumbledore's in the frame."
"No, I ruled him out a few days ago."
She laughed, and then said suddenly "I've missed you. You're twisted in all the right ways."
"And you're twisted in several wrong ones."
"Takes all sorts to make a world, you know." She hefted the invisibility cloak, as they neared the Hogwarts end of the tunnel. "I should be getting back."
"Yes, you should," he agreed shortly. She laughed again.
"What, no chivalrous offer to walk me back to my dorm?"
"Yes, because sneaking around by the Gryffindor girls' dorm is exactly where I want to get caught by Pringle."
"I don't know," said Lily, smiling; "might be a good idea to get some rumours started. Add to your aura of mystique."
"It'd put your boyfriend's nose out of joint."
"He's not my boyfriend."
"So you frequently protest."
They went their separate ways.
Malfoy was waiting up for him in the boys' dorm; Avery had long-since dozed off.
"You're late," he observed, with calculated neutrality.
A lie was never so good as a half-truth. "I ran into some... complications in Hogsmeade."
"Complications?"
"Potter and his little gang."
"Potter?" Malfoy looked furious. "That little Muggle-lover pops up entirely too much for my liking. We can't have him interfering with our operations, Severus. That could ruin everything."
"There's not a lot you can do about him, Lucius," Sev pointed out. "The whole school knows you're enemies. If anything happens..."
"If anything happens, it'll have to be possible to blame it fairly and squarely on somebody else," Malfoy completed. Sev nodded slightly, wondering what he was plotting.
"Who exactly did you have in mind?"
Malfoy smirked. "Oh, there's a little... event... going down in the near future. Some friends of ours are gonna be coming over, and I don't know, I think we might just be able to persuade them to give us a bit of a hand."
He smiled tigerishly, and lay back in his bed.