Small chapter for in between Season 3 and Season 4. I'd like to thank my amazing, wonderful beta nightgigjo. Nothing about the last chapters would have been as good as they are if it wasn't for you.

As always, thank you to those of you that read, favourited, followed or reviewed the last chapter.

Disclaimer: All the characters displayed in this fic belong to their respective creators, JK Rowling (Harry Potter), Moffat and Gatiss (BBC Sherlock), and Sir Arthur Conan Doyle (Sherlock Holmes).

Note 01/04/2021: Edited.

Chapter 19: A dance with the devil

Hermione woke up without being aware that she had fallen asleep. Her head was pounding, her mouth was pasty, and it was difficult to open her eyes. Next to her, Siger was snoring lightly. Confused, she got up and went to the kitchen, where she saw Mycroft with his head on the table and Margaret in a deep sleep on the couch. She looked around and left the kitchen in search of the others. When Hermione reached the little sitting-room at the back of the house, she saw Mary lying on the sofa, her feet up and Billy beside her, flipping through a heavy red book. But there was no sign of Sherlock or John.

'Billy, what's happened to us?'

'Nuffin', just a lil' summit in yer punch ter relax ya,' said Billy without lifting her head. Hermione approached Mary and shook her lightly. Once she saw that she didn't wake up, she turned to Billy.

'Where are John and Sherlock?'

'They ain't 'ere,' said Billy. Hermione felt her heart skip a beat and an invisible hand squeezed her chest. Still, with muscles stiff from whatever Billy had administered to them, she returned to Mycroft's side. Behind her came Billy. Hermione reached under the cold tap water and splashed water onto Mycroft's face.

'Where did they go?'

'Shezza didn't say. Summit abaht a devil.' Billy disappeared into the other room, leaving Hermione trying to wake Mycroft, who slowly became conscious.

'Hermione?' Mycroft looked into her eyes.

'Mycroft, Sherlock and John are gone. I think it has something to do with 'Magnussen.'

'What?' Mycroft shook his head, trying to get the last traces of the drug out of his system. He scanned the table and picked up one of the nearby napkins. 'My laptop. Sherlock must have taken it with him. To bargain.'

'But your laptop has GPS,' observed Hermione.

'Yes, and he knows it.' Next to them, Margaret had started stirring, and Mycroft was already reaching into his pockets for his phone. 'I think he wants to frame Magnussen.'

Hermione looked at the eldest Holmes. 'Do you think it can work?'

'If there's something I've learned about Charles Magnussen,' Mycroft said, while pressing the call button and putting the phone to his ear. 'Is that you never know what aces he has up his sleeve.'

At an MI6 undisclosed location, inside a small and dingy room several stories underground, Hermione waited. The air smelled of dampness and stale water, and the barely illuminated walls seemed to weep with humidity. She had been forced to hand in her phone and her watch when she arrived, and she did not know how long he had been there. Her gun and wand had also been taken away, maybe worried of what could happen between those four walls if she kept them. Her nails, which hours before had been perfectly manicured, now had rigged edges and were barely making a sound when Hermione taped them impatiently against the metal table. She caught a glance of herself on the one-way mirror in front of her. She didn't make a pretty sight. Heavy bags under her eyes and splotchy face, hair tied in a messy bun. She felt a thousand years old.

Behind her, the hinges screeched as the door opened, and she leapt to her feet. Sherlock was at the threshold, followed by two guards, each of them with a hand on the detective's shoulders, pushing him inside. Sherlock seemed to be as tired as she was. Hermione had been told very little about what had happened after Mycroft had left the Holmes' cottage in a helicopter, but she could hazard a guess. And looking at Sherlock's suit, with speckles of dried blood adhered to the expensive fabric, she knew she was right.

One of the guards led Sherlock to the other chair and tied the handcuffs around Sherlock's wrist to the small bar on the table before leaving them alone. Only then, when no one else was in the room, Sherlock raised his head and looked at Hermione.

'It had to be done, Hermione,' said Sherlock finally.

'You should have told us,' snapped Hermione. 'We could have found a way of defeating him.'

'It wouldn't have mattered. Don't you see? I made a mistake.' Sherlock tried to raise his hands, but the short link of the handcuff stopped his gesture mid-motion. The clanking round of metal against metal filled the room. 'There were no vaults. It was all him, inside his head. His mind palace. No matter what we came up with, he would have always had the upper hand.'

'Mycroft could—'

'He wouldn't have been able to. Not with the kind of security Magnussen had and the precautions he was taking. Mycroft wouldn't have been able to protect you.'

Hermione frowned. 'Me?'

'He knew about you, everything about you. He knew Mycroft would never let anything happen to you, so you were his new target. He wanted to use your… abilities as leverage.' Sherlock opened his hands in a defeated gesture. 'Now you and Mary are safe.'

'For Christ's sake, Sherlock! Mary and I will never be safe.' Hermione smashed her hands on the table and stood up. 'This wasn't your fight! You should've trusted me; you should have let us know!'

'I could not!' There was the rattle again, and Sherlock lowered his head to rack his hands through his dirty hair. 'You would have done anything to help Mary. You would have put yourself on the line, and I could not let that happen.'

Hermione stared at the man. The dimension of Sherlock's feelings, of how much he cared, had had consequences they should have seen coming. The lengths he would go to end a case, to protect whoever needed protecting. But at some point in Appledore, the problem had stopped being about Mary and had shifted to her. Magnussen had threatened her, and Sherlock had murdered him for it.

'Why?'

Sherlock looked at her, his tired blue eyes blinking and shifting to his hands and then back to her. 'You know why.'

'No, Sherlock. You tell me.'

'I can't.'

Hermione's lips curled in a scowl. 'You are a coward, Sherlock,' she managed to spit out.

'What do you want me to say to you, Hermione? I don't have words for this! Everything I know is that I would have rather burned in hell before I let that monster get to you.'

The strength in his tone made Hermione shiver. Maybe she did not need to hear it; perhaps not even he could put words in what simmered between them. But the fierceness of his feelings was undeniable. He might have made the wrong choice, but Hermione did not remember when was the last time someone put her safety over everything else. She circled the table, her eyes on Sherlock's, who followed her every move. Hermione sat on the table next to him and tentatively reaching for Sherlock's hands. Feeling his warm skin against hers again was electrifying, and she fought the urge to sink them in his hair.

'What's going to happen now?'

Sherlock interlaced his fingers with hers. 'I am leaving on a mission. No return date. Tomorrow.'

Hermione nodded, her stomach sinking. He's not returning alive, she thought, and she understood why he was so deliberate with his touch, with his words. He had nothing else to lose. Suddenly, the thought of not seeing his eyes anymore constricted her throat, and tears started welling in her eyes when she squeezed his hand. He remained stoic, but his pulse, wild and fast, betrayed him. Hermione gripped his hand.

'I'll be there.'

'No,' said Sherlock.

'But Sherlock—'

'No, Hermione. Please, do me this kindness,' begged Sherlock. 'I asked Mycroft to bring you here because I don't want your last image of me to be jumping on a plane.' Sherlock regarded the room. 'It's not what I would have liked, but I thought a private explanation was the least I could do.'

Hermione put a hand over his cheek, her thumb gently going over the bone. The scruff scratched her palm, and she briefly wondered if she would remember the feeling. Sherlock must have heard something she had missed in her reverie because he averted his gaze seconds before the door opened again. Hermione turned and saw the same guards entering. One of them went to free Sherlock from the table.

'Agent Black,' said the guard close to the door. 'A car is waiting for you. We are taking Mr Holmes to a secure location.'

Hermione could recognise an order to leave when she heard one, but she was rooted on the spot, frozen. The other guard pushed Sherlock towards the door, with Hermione following behind. The three men moved towards the corridor to their left, and a different guard outside stopped Hermione outside the room. She stood there, watching Sherlock leave, and she realised two things:

That Sherlock was going to die and that even Mycroft's power had limits.