Inside her cell, Eurus smiled at Sherlock as he pocketed his earpiece, before she said calmly: "Let's continue."

Eurus stopped a few steps from the edge of her glass prison, asking Sherlock: "Did they tell you to keep three feet from the glass? "

"Yes." Sherlock answered, not even looking at the stenciled warning reminders on each glass panel around Eurus's cell. He didn't need to be reminded, so he did not need to do something so trivial – instead, he kept his eyes on Eurus.

"Be naughty. Step closer." She ordered, and Sherlock raised his brows as he asked pointedly: "Why?"

"Do it. Step closer." She insisted, and Sherlock paused as he examined her.

Instead of complying, however, Sherlock asked abruptly: "Tell me what you remember."

"You, me, and Mycroft." Eurus answered flatly. She sighed slightly before adding: "Mycroft was quite clever. He could understand things if you went a bit slow but you... you were my favourite."

Sherlock took a small step forward, before bringing his feet together once more as he prodded: "Why was I your favourite?"

Eurus mirrored his actions, taking one step forward, closer to the edge of her prison as she answered almost breathily: "'Cause I could make you laugh. I loved it when you laughed. Once I made you laugh all night. I thought you were going to burst."

Sherlock smiled tightly, though his eyes were still fixed on Eurus suspiciously as she murmured: "I was so happy."

Sherlock took another small step forward, while Eurus continued: "Then Mummy and Daddy had to stop me, of course."

"Why?" Sherlock asked, and Eurus answered as she also took a step forward: "Well, turns out I got it wrong. Apparently, you were screaming."

She looked confused, thoughtful, but Sherlock took it in stride as he questioned without emotion: "Why was I screaming?"

But his mind answered for him, and Sherlock stiffened as he heard a dog whining faintly in the back of his mind.

"Redbeard." He realized, and Eurus tilted her head as Sherlock lowered his gaze slightly.

Desperately reigning in his emotions, Sherlock met her gaze again as he informed his sister: "I remember Redbeard."

"Do you, now?" Eurus challenged in a soft purr as she stepped even closer, and Sherlock mirrored the action as he demanded: "Tell me what I don't know."

The two siblings were very close now, almost face-to-face against the edge of Eurus's cell. Eurus's eyes were burning as she stared up at Sherlock while he looked down at her, meeting her gaze squarely though his hands twitched slightly, wanting to curl into fists against the wave of uneasy emotions inside him.

"Touch the glass." Eurus ordered suddenly, and Sherlock frowned at her.


Inside the Governor's office

"I put my trust in you, my implicit trust." Mycroft was saying angrily to the Governor. "As governor of this institute!"

"It's obvious when it all started." The Governor retorted. "Well, she was never the same after that Christmas. It's as if you woke her up."

"That is entirely beside the point." Mycroft snapped. "You had your orders and failed to act on them!"

"Listen to the tape." John ordered abruptly, removing his hand from his earpiece once more.

"Sorry?" Mycroft asked, frowning as he glanced at John, who insisted: "Do it now. Listen."

Mycroft rolled his eyes as he began: "My sister's methods of-"

"Just listen." John hissed, and Mycroft paused, his frown deepening as he stared at John while onscreen Eurus said: "You have no idea how I could help."

John was staring intently at the screen, so with a sigh Mycroft returned to the Governor's desk, picking up the remote and increasing the volume as Eurus continued to say: "Bring me your wife. I want to meet her."

"I don't need your help." The off-screen male replied flatly, his voice more distinct now that they could hear him as well.


In Eurus's cell room

"Redbeard was my dog." Sherlock said slowly as he examined his sister intently. "I know what happened to Redbeard."

"Oh, Sherlock, you know nothing." Eurus answered as she stared up at Sherlock, who pursed his lips tightly. "Touch the glass, and I'll tell you the truth."

Sherlock frowned at her insistence that he touch the glass, and Eurus lifted her left hand as she offered: "I'll touch it too, if you're scared."


Somewhere inside the facility

Marie sprinted without a sound down the hallways, keeping out of sight of the guards once again lining every corridor as she stuck to less crowded areas while silently taking down any guards she happened upon.

She was careful, not wanting to raise the alarm prematurely, but it slowed her down; and that was something she couldn't afford right now.

Two minutes earlier

"Vatican Cameos." John said over their earpiece, only for Sherlock to dismiss him impatiently.

And almost as soon as Sherlock disconnected from them, after John's warning, the guards started to move. Marie promptly turned and rushed back into the facility, and she warned as she ran inside: "John, get out of there."

"Wait, there's something I need to check." He replied, switching his earpiece on so Marie could hear everything on his side before he turned to Mycroft.

Present

Marie took down another guard, catching his unconscious body before he could fall and make a noise, while she listened in on John's side of the earpiece.


Inside the Governor's office

"I can fix her for you," Eurus was saying onscreen, "and then I'll give you her straight back, good as new. I promise."

"That's all?" The man off-screen asked, his voice shaking slightly. "What you're proposing is not... it's not right."

John turned to look at the Governor as he pointed out: "Everyone who went in there got affected - 'enslaved', you said."

"Yes." The Governor agreed, not meeting John's eye as he shifted in his seat while staring at the screen.

"One after the other." John added, and the Governor confirmed: "Yes."

"Dr. Watson," Mycroft began with a frown, "I think we've-"

"Shut up." John interrupted flatly, causing Mycroft to shoot him an incredulous look, but John had turned back to the Governor as he said: "One question - that's your voice, isn't it?"

He pointed at the Governor, who had turned to look at him before he looked back at the screen where Eurus was saying: "Do you really? Do you trust her?"

"You've got to stop saying these things." The Governor's voice replied tensely, and John pointed out sharply: "If Eurus has enslaved you, then who exactly is in charge of this prison?"

Mycroft also stared at the screen in shock as the Governor's voice said off-screen: "It's completely inappropriate."

The Governor stood up quickly, and he stated as his hand reached inside his suit jacket: "I'm sorry."

He removed a small remote in his hand, and John flinched: "No."

"Very, very sorry." The Governor repeated as he looked right at John, while Marie yelled in John's ear: "John, get out of there!"

"No." John said, though even he wasn't sure if he was replying to the Governor or Marie.

It didn't matter; the Governor pressed the button on the remote, instantly setting off the facility's alarms. Sirens blared while armed guards came rushing into the office, guns aimed at Mycroft and John who both quickly raised their hands in surrender.

"John!" Marie yelled, and he retorted swiftly: "Save Sherlock!"


In Eurus's cell room

"You think it's a trick." Eurus whispered as she stared at her brother. "You look so... unsure; you're not used to being unsure, are you?"

"It's more common than you'd think." Sherlock returned, matching her gaze, but Eurus didn't rise to his comment as she murmured almost pitying: "Look at you."

Sherlock slowly lifted his right hand, reaching it out towards Eurus's as she continued softly: "The man who sees through everything... is exactly the man who doesn't notice..."

Their hands touched, and Eurus instantly connected their hands, linking her fingers through Sherlock's with a mocking gasp of feigned surprise.

"… When there's nothing to see through." She finished while Sherlock's breathing hitched as he glanced at their interlocked hands before looking back at Eurus as she smiled at him.

"Do you see how it was done?" Eurus inquired. "I know you like explanations."

Sherlock blinked rapidly, glancing down as he reread the warning scripts that he'd assumed were on glass panels all around Eurus. It was only now that he realized they were mounted and projecting sideways from the empty panel frames.

"Signs." Sherlock breathed as he looked back at Eurus. "You suspended the signs."

"And my voice?" She asked, anticipating where his mind would move next. "Throat mic. Puts me through the speakers."

There was a click, and the speakers cut off while Eurus continued in her regular voice: "Don't you think it's clever? Simple but clever?"

"Transparent." Sherlock answered, his voice shaking as he realized very belatedly that things were going very, very wrong. Marie and John had tried to warn him… and now, he realized it might be far too late.

"Well, you do keep asking me how I got out of here." Eurus taunted, before finally unclasping her fingers from Sherlock's and she slowly pulled her hand away as she whispered: "Like this."

She abruptly sucked in a harsh breath before swinging both her arms up sharply to slam her fists on either side of Sherlock's head, above the temples.

Sherlock grunted as he fell backwards onto the ground while his head spun and his ears rung, before he choked as Eurus slammed herself on top of him, her right arm crushing down on Sherlock's throat while she screamed viciously in his face.

Sherlock choked, unable to breathe or fight back as Eurus held his arms and legs down with her whole body while she screamed: "Get in here, all of you! Stop me killing him!"

Guards rushed in as the elevator doors opened, far too quickly for them not to have been waiting there since some time after Sherlock had arrived.

The thought passed vaguely through Sherlock's mind as he struggled to breathe, while Eurus lifted her head to say, eerily calmly to the guards: "No, no. Stop me in a minute."

She then looked back down at Sherlock as he choked and gasped, and she screamed in his face again while his face turned purple as she continued to strangle him.


Inside the facility

John waited until he was led out of the Governor's office, away from the guns guarding the Governor, before he kicked the two guards holding his arms. The guards yelled in pain, their grip on John faltering for a moment.

Quickly swinging around as he broke free of their grasp, John punched one guard before head-butting the other. The guards fell, knocked out, and John dashed away quickly for the stairs while Mycroft started to struggle against his own guards just as an American-accented voice announced over the speakers: "Red alert! Red alert! Big bad bouncy red alert!"

"Dr. Watson!" The Governor called after John, but he ignored the man as he raced away, trying to find Marie or Sherlock so they could escape before...

"Klingons attacking lower decks!" The intercom continued to call.

Mycroft paused in his struggling, looking up at the nearest speaker in horror as the voice continued: "Also, cowboys in black hats, and Darth Vader!"

John paused as well, slowing down on the landing near the security camera room as the voice he would never, ever forget chirped over the intercom: "Don't be alarmed! I'm here now! I'm here now!"

John turned to look inside the security room, and he pointed in confusion while his jaw dropped in shock as the face of Jim Moriarty appeared on every screen, saying blithely in his normal tone: "Did you miss me? Did you miss me?"

John didn't even have time to blink when something hit the back of his head, hard. John collapsed, falling backwards with his eyes glazed over as Jim's voice continued to ring: "Miss me? Miss me? Miss me?"


Elsewhere in the facility

Marie spun around, firing a bullet per second as she took down all the guards that had tried to surround her. But each time one fell, another took his place; Marie dodged and ran about, avoiding the tranquilizers shot her way while she fired, reloaded when she ran out of bullets, and repeated the sequence.

It was a tedious task more than an actual fight, made no less irritating as Jim's voice continued to chirp all around them: "Miss me? Miss me? Miss me?"

Marie shot another guard, leaving only three left amongst the piles of unconscious bodies, when Jim's voice suddenly sang: "Oh, dear, dear, dear, Vicky, you're being such a naughty girl."

Marie stopped in the middle of aiming at her next target, her eyes narrowing as the guards all kept their guns aimed at her while Jim's voice continued: "What would Sherlock say if John Watson ended up dead because of you?"

Her jaw clenched and Marie's green eyes flashed dangerously, while Jim's voice continued: "Oh, but that won't matter – you know better than to care about other people, right? So it's all right if John Watson dies if you can save yourself."

"Put your weapon down!" The guard ordered, and Marie glared at the man while Jim's voice said in feigned apology: "Oh, wait, I forgot! You love Sherlock, though, don't you? And you don't want John Watson to die… him, or Molly Hooper, or the great Inspector Lestrade."

"Put your weapon down!" The guard repeated as Marie's teeth ground, while Jim's voice went on: "You started to care; you became weak."

His voice turned dark as he said lowly: "You forgot my lessons, naughty girl. You must be punished…"

Marie took a deep breath, before dropping her gun and letting the guard shoot her with a tranquilizer as Jim's voice breathed: "… For giving yourself weaknesses."


John slowly opened his eyes, blinking several times as the world swam around him. When his vision finally came back into focus, John grimaced as his head pounded feeling like someone was smashing his brain with an anvil.

Lifting his head, John placed a hand on the source of his pain at the back of his head before he looked around. He was lying on a bed somewhere, while Mycroft leant against the wall nearby, his chin propped on his hand in thought. Marie stood beside him, also leaning on the wall though her arms were crossed across her chest. Across the room from them, the Governor sat curled in the corner, his knees drawn up against his chest.

Sherlock had been pacing the length of the strange room they were in, though he kept himself closest to Marie as he walked. He stopped when John lifted his head, turning to his friend and asking: "How are you?"

Marie also turned to look at him, while Sherlock resumed pacing and John winced before he answered: "Bit of a lump."

"True that, but you have your uses." Sherlock answered casually as he turned and paced once more along the length of the glass wall caging them into the cell. A cell that looked identical to Eurus's, and probably what hers had originally looked like before she removed the glass.

"Did you see your sister?" John inquired as he sat up on the bed, and Sherlock replied shortly: "Yes."

"How was that?" John asked, glancing at his friend, and Sherlock took a deep breath before answering: "Family's always difficult."

"She tried to strangle him." Marie explained, and John answered: "Ah."

"And she had Marie shot. Again." Sherlock added, and John looked quickly at Marie in alarm but she waved it off as she elaborated: "With a tranquilizer."

"Mm." John hummed, before turning to Sherlock as he advised: "I think it's just your family that's always difficult."

"Is this an occasion for banter?" Mycroft sighed at them, and Marie gestured at the eldest Holmes sibling as she added to Sherlock: "Case in point."

Sherlock nodded in agreement while Mycroft pursed his lips, when suddenly the sound of a phone dial sounded around them.

"Are we phoning someone?" John asked in confusion as he stood up, and Sherlock muttered as he glanced up at the security camera mounted on the ceiling in the corner: "Apparently."

Marie also glanced at the security camera before looking towards one of the speakers set up around the room while John looked across the cell at the Governor.

"What's he doing here?" He asked, frowning in confusion, and Sherlock explained without even looking: "As he is told."

He finally stopped pacing, standing beside Marie as he turned to look at John, adding flatly: "Eurus is in control."

The phone connected at that moment, and Marie inhaled sharply as a young girl called tearfully over the speakers: "Help me. Please, I'm on a plane and everyone's asleep. Help me!"

The call abruptly cut as quickly as it had started, while Sherlock's lips parted and Marie's entire frame tensed.

The lights in the cell suddenly turned red, giving the room an eerie glow while Jim's voice drawled over the speakers: "Hello. My name's Jim Moriarty. "

Mycroft sighed heavily while Sherlock, John, and Marie exchanged looks as Jim said jauntily but darkly: "Welcome... to the final problem."