When Hermione and Draco approached Severus about the mysterious warning she had received through the post, he was rather sceptical about the entire thing. His first thought was that the letter was a trap, and whoever had sent it was hoping the dark would concentrate so much of their time and resources on protecting Hogwarts that they would leave themselves open to attack elsewhere, the Ministry of Magic for example. When he shared the news with Voldemort and Lucius, Voldemort's instincts were the same as Severus's and he was highly doubtful that the warning was genuine.
However, what all three wizards agreed on was genuine or not, the letter had inspired Hermione to remember the numerous secret passageways in and around the old castle, and that something should be done to plug the weaknesses in Hogwarts defences. Very aware that if the letter was a trap, they didn't want to be seen falling into it, the passageways were dealt with so subtly that anyone who might be watching the castle wouldn't nothing anything was amiss.
As well as the passageways Hermione had mentioned, Voldemort had been able to identify a couple of old tunnels he'd used in his time at Hogwarts. Lucius had also provided the location of two secret passageways, one of which he proudly announced he used to use to visit Narcissa once he'd left Hogwarts and she was in her seventh year. Bellatrix had also provided information on a different passageway she knew about, and other Death Eaters had been quietly asked for their knowledge on secret passageways in and around the school.
Armed with as much knowledge as they could muster, Severus and Lucius set out to secure each and every passageway, even though they found several of them were now inaccessible. Even so, every passageway, usable or not, had been blocked off from the Hogwarts entrance. And at the other ends of the passageways, subtle wards had been erected to alert them to anyone trying to use the passageway. As for the tunnel leading to Honeydukes, they'd paid the shopkeeper to explore his cellar, and once the tunnel had been located, they followed it through to Hogwarts and discovered its entrance. Then like all the others, that entrance had been blocked and wards erected around the side that ran from Honeydukes cellar.
Not wanting anyone to get wind of what they were doing, meant it took a couple of weeks for all the known tunnels and passageways to be secured. However, the one passageway which got the most attention, was the one leading from The Shrieking Shack. Everyone agreed that if the letter was genuine, the Shrieking Shack would be the perfect base for The Order to work from. And of course from there they could access both Hogwarts and Hogsmeade. As such, several wards had been erected around The Shrieking Shack, some which would alert Severus and Lucius if anyone even entered the building, and others that would alert them if the tunnel leading to Hogwarts was used.
Just over two weeks after starting their project to secure the castle, on the Friday evening, Severus was meeting Lucius down in Hogsmeade to run over all the passageways they'd found, and to check they hadn't missed any. Still wanting to keep things under the radar, the two wizards had arranged to meet up publicly in The Three Broomsticks, and they would be joined by Narcissa and Bellatrix, making it seem like a social occasion to anyone watching.
When Severus and Bellatrix arrived at The Three Broomsticks, they found Lucius and Narcissa had already arrived and had nabbed a table beside the window. The pub itself was fairly quiet, and no-one was sitting anywhere near the two Malfoys, although Severus wasn't sure if that was the reason Lucius had picked that table, or if he'd done something to keep other people away. Either way it didn't really matter as the table afforded them some privacy, and that was all they wanted.
Drinks were already waiting for them, and Severus and Bellatrix settled down at the two empty chairs. While they drank they kept the conversation general, with Lucius and Narcissa both keen to hear how Draco was doing in school and how he was faring in his Aunt's Dark Arts lessons. Eventually talk turned to the reason they were meeting, and Lucius produced a rough map of Hogwarts he'd knocked up at home.
"I've marked off each passageway we've dealt with," he explained. "And checked them off the list we made when we received information. By my reckoning every passageway we know about has been dealt with. But we do have a few rumours we haven't been able to get more information on. I was thinking looking at a map and taking each rumour one at a time, might help us. We might find, we've already dealt with that particular passageway."
"Sounds like a plan to me," Severus agreed with a nod of his head. "I'll go grab us some more drinks and we can get started."
Heading to the bar, Severus placed his order and the first of their drinks had just been put on the bar when Lucius barrelled over to him, and grabbed him by the arm.
"Come with me," he hissed, dragging Severus away from the bar.
"The drinks, I haven't paid yet," Severus protested as his friend steered him towards the toilets out the back of the main bar.
"Cissa will take care of it," Lucius said. "You need to come with me."
Lucius pulled Severus past the toilets, down past a door marked staff only and out of the back entrance. Without stopping, he steered Severus through the back yard of the pub and out into the back streets of Hogsmeade. Hurrying down the street, he ducked into an alleyway between two shops and finally came to a halt, mere inches from the front of the alleyway.
"What are we doing?" Severus hissed at his friend.
"Watch," Lucius replied.
Severus was just about to ask what he was supposed to watch when two figures came into view in the street in front of them. At first Severus didn't give them a good look as it was hardly suspicious to be walking around Hogsmeade on a Friday evening, but then he realised they both had red hair. As they passed by the alleyway he and Lucius were standing in, Severus inched forward and peered out into the street, watching the two wizards as they disappeared around the corner at the bottom of the street.
"Weasleys," he said softly.
"I thought so," Lucius said with a bob of his head. "Let's follow them."
Moving back down the alley, so they were using the back streets, the two wizards quickly caught up to the two Weasleys. While the pair weren't hurrying along with a purpose, nor were they dawdling, meaning it was fairly easy for Lucius and Severus to watch them without having to get too close. After less than a minute it became obvious where they were heading when they turned out of the main part of the village and started to walk up the path that would eventually lead them to the Shrieking Shack. Since that path was very open and it would be impossible to follow them without being seen, especially Lucius who would stand out a mile with his hair, Severus and Lucius stayed hidden behind the shop on the corner of the street, and neither were shocked when their wands alerted them to the fact the wards around The Shrieking Shack had been breached.
"Maybe the letter was more reliable than we thought," Severus mused as the two wizards turned to head back to the pub.
"It does seem that way," Lucius answered with a nod. "I take it that was the oldest two Weasleys."
"Yes, that was Bill and Charlie," Severus replied.
"What are they like?" Lucius asked, having never met either of the two older Weasley children, but knowing that Severus had taught them both. "Are they going to be trouble?"
"Neither of them are to be underestimated," Severus warned. "Both of them are pretty smart. Bill was Head Boy, and he went off to be a curse breaker."
"Which takes skill," Lucius remarked.
"Skill he has," Severus confirmed. "And so does Charlie. He wasn't as academic as his brother, but he was just as clever. His passion was animals, and he rushed off to a dragon sanctuary mere weeks after graduation."
"Hmm, a dragon tamer and a curse-breaker, both impressive, and as you say, not to be underestimated," Lucius mused.
Re-entering the pub, the pair rejoined Narcissa and Bellatrix, and within two minutes of them sitting down they received another alert to say the wards around The Shrieking Shack had been passed through. Quickly filling the two witches in on what was happening, a third alert sounded just as they reached the end of their tale.
"There's at least four people in there now," Bellatrix remarked when Severus mentioned the third alert.
"And that's if the second two alerts were only for a single person," Lucius said. "But at a minimum, we've got four people who are clearly up to no good holed up in that dirty shack."
"I think we should get back and alert The Dark Lord," Narcissa said with a frown. "They could be trying to sneak into Hogwarts as we speak."
"They're not," Severus assured the clearly concerned witch. "The wards around the tunnel leading to the castle haven't been breached. I think for now, they're settling in and going over whatever plan they've got."
"In that case, we need to be forming a plan of our own," Lucius said. "Severus, go back to the castle and bring Hermione and Draco to the manor. If Potter does have a map of the school, we don't want to alert him to anything by turning up at school. But it might not be too suspicious if Hermione and Draco go missing for a few hours. They'll likely just think you're giving them special treatment and allowing them to make visits home."
Agreeing with Lucius that it would be unwise for anyone different to suddenly appear in school, Severus finished his drink before he and Bellatrix set off back to school. Thanks to the wards they'd set up in the Shrieking Shack, he knew no-one had tried to enter the tunnel to get to Hogwarts, so even though the threat was present, it wasn't imminent and there was no need to rush and make a rash decision. At that moment, they had the upper hand as they knew Potter and his friends were up to something, and they would know when they made their move.
"Go and get Draco and Hermione," Severus ordered Bellatrix when they reached the castle. "I'll activate the floo in the Potions Master's office."
Technically as headmaster, Severus had the use of the Head's office, and he was in the middle of turning that space into his own. But for now, he was still most comfortable down in his old office, especially since he was still teaching Potions as well as acting as Headmaster. Besides, it was faster to bring Draco and Hermione to his office down in the dungeons than have them trail halfway around the school to reach the Headmaster's office.
By the time the floo was set up, Bellatrix had returned with Hermione and Draco in tow. Of course both teenagers were full of questions, but all Severus informed them was that there was a threat that needed dealing with. Reminding them that the quicker they went through to the manor, the quicker they would find out what was going on, hurried the pair up and they led the way to Malfoy Manor, with him and Bellatrix following behind.
When they arrived, Lucius had already gathered Voldemort and Leah, and it was clear that he'd at least given them an idea as to what was going on. As everyone else took their seats, Lucius brought Hermione and Draco up to date with what they'd witnessed in Hogsmeade.
"So there's at least four of them up at the shack," Draco mused.
"I would say six minimum," Hermione corrected. "Quite possibly seven."
"Why six?" Voldemort asked his daughter.
"Severus has already identified Bill and Charlie," Hermione began. "Harry and Ron will most certainly be involved. And I would think Sirius would be there to support Harry. And if Sirius is there, chances are Lupin is there as well. I would be surprised if any of them were missing from the group hiding out in the shack."
"What about the possible seventh?" Lucius asked.
"Ginny," Hermione answered. "Her brothers are usually pretty protective of her, but she certainly shouldn't be counted out in a fight. She's a pretty handy witch. And given what had happened recently, she would have a reason to want to fight. If she pushed hard enough, I think her brothers would have allowed her to join them."
"So we think we're facing six, possibly seven, opponents," Voldemort muttered as he paced the floor rather than sit beside his wife. "But it could be more, or it could be less. And there's still been no move towards the tunnel into Hogwarts?"
"No, that ward hasn't been breached," Severus confirmed. "And I've received no alert to say they've left the shack, either."
"So they're sitting tight, possibly planning something," Leah said. "But how are we supposed to know what they're planning? From that shack, they could target Hermione at school or at Hogsmeade."
"And it is a Hogsmeade weekend this weekend," Draco reminded everyone.
"Would they really try something in Hogsmeade?" Hermione questioned. "Especially after last time with Draco. Making such a public move wouldn't be smart."
"I do agree, it doesn't seem likely," Bellatrix agreed. "Especially since they've hidden themselves away in the shack. They don't want anyone to know they're there."
"Which means they aren't likely to do anything public," Narcissa said. "It does seem to back up the information Hermione received in her letter about Hogwarts not being safe. It seems more likely they'll try and attack there."
"It does," Voldemort agreed with a nod. "Thanks to Severus and Lucius we'll have a small window of warning though. We'll know when they enter the tunnel to reach Hogwarts."
"But that doesn't give us much time to reach Hermione," Leah said snappily. "My daughter could still be hurt before we reach her. I don't like the idea of just sitting around and waiting for them to make their move."
"Then we make them move when we're ready," Voldemort said, a sly smirk breaking out over his face. "We know they're there, so we use that to our advantage. Instead of waiting for them to come at us, we bring them to us."
"And how do we do that?" Hermione asked.
"By using this map of Potter's to our advantage," Voldemort replied. "We all agree they won't make any move at Hogsmeade, so let's use the fact most of the school will be down in the village. Let's give them a chance to get to Hermione. Let's lure them into school, by letting them think she's alone."
"But surely for that to work, she will have to be alone," Draco pointed out. "Potter's map would show if anyone was hiding nearby."
"No-one will be hiding nearby," Voldemort said. "I think tomorrow, Hermione should be left at school while everyone else goes down to Hogsmeade. Thanks to Lucius and Severus, we'll know when Potter and his friends make their move. So while they're making their way onto the school grounds, everyone else can be sneaking back using one of the other passageways. We just have to be careful not to enter the school before Potter and his friends. They'll then corner Hermione, but before they can do anything, they'll find themselves trapped."
"If you pick the right place in the school that could work," Hermione agreed with a thoughtful nod of her head. "But what if they don't want to move during daylight? Even with so many students down in Hogsmeade, there's still a high risk of someone seeing them. In their shoes, I wouldn't risk moving in daylight."
"Then we come up with a back-up plan in case they wait for the cover of night," Voldemort said with a shrug. "Either way, you are not going back to that castle until we have some solid plans in place. I will keep you safe, Hermione, even if it means storming that sodding shack, killing everyone inside and starting an uprising against us."
"Let's call that plan c," Hermione remarked, well aware that her father was serious and if there was no other option, he would happily take out the problem at the source. However, in Hermione's eyes it would be better to deal with problem quietly and with the minimum of fuss. "Plan a was coming along nicely, so let's make a plan b."