A/N: This chapter is quite dark, so if you're of a sensitive nature then skip ahead. It just details Missy's side of Extremis. Extra long chapter this week! Thanks - L x

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"Quite nice in here actually, isn't it?" Missy commented, trying to make some sort of distracting conversation with the guard that stood opposite her. They had her locked in some sort of tower-type prison, God knows where. It was medieval looking, with stubby, stone walls with long chains attached. It was to these chains that Missy's hands were bound as she kneeled on the floor. In front of the door stood a Heriotza guard, holding a spear and without his helmet. He looked sternly ahead, blatantly ignoring the Time Lord that continued to have a one-side conversation with him and herself. The guard had pale skin and ruddy cheeks, with thick, blonde hair that went past his shoulders. A dark bruise encircled his eye.
"Do you do this for everyone?" Missy lulled, hanging off the chains. "Or am I special?"

"Please... Be quiet", the guard answered in a low voice.

"I thought that if I went quietly and didn't kill any of your guards, you'd treat me a little better. Surely, three men's lives are worth a small conversation?" Missy asked with a small smile. "Go on. I'm going to die soon, can't I die without being bored?"

The guard didn't respond, just tightened his grip around the spear in his gauntlet. Missy slumped back down the wall. The two stayed in silence until there was an abrupt clank of the door and it opened. With his unchanging expression still looking into space, the guard turned and stood away from the door. The sunlight beamed in and made Missy wince, her eyes used to the dark of the tower. Unlocking her manacles, she shot the guard a maleficent glare, and lifted her finger to his chin, digging in her painted black fingernail. "When I get out of here, and I will", she started, forcing his face closer to her own and dropping her voice to just a whisper. "I'll tear this organisation apart and I'll start with you".
No, no, this wasn't her. This wouldn't be what The Doctor wanted. This was The Master talking. Oh, who was she kidding. The Master was right. She couldn't help herself. She was fighting her past and she was losing. Did she really think that she could change just like that without any consequences? This was her. She was ripping out a part of herself that she had always relied on, that she built a reputation on. Simply, she couldn't help being bad. It was like a drug. With all of the horrors that she had seen and caused herself, being bad numbed it all. And she was addicted to the feeling.

"The Heriotza spans across galaxies and universes, past and future. We have destroyed entire generations, races... Do you really think a little Time Lord like you will break us down?" Missy didn't answer. She didn't want to know the words that could come from her lips. "I thought not". He began to walk through the door, but paused and chuckled to himself.

"Is something funny?" Missy asked in a harsh tone.

"No, it's just... Sad. Hundreds of years of the Last Great Time War and the only two to survive are the coward and the madwoman. All those fighters and incredible minds...gone".

"You have no right", Missy hissed under her breath. "The Doctor was brave; he did what was necessary. He was in no way a coward".

"He took the easy road out when he burnt Gallifrey to the ground. He could have fought on. He betrayed your kind. And yet you still defend him". Missy laughed to herself. Obviously the news that Gallifrey lived was slow spreading, or nobody bothered to check.

"I have no reason not to. He is everything I am not and everything I wish to be".

"You wish to be a menace to the universe. To fail your kind repeatably?"

"I already have", Missy answered quickly. "Perhaps him and I are more alike than I realise. Or you are too blind to see the good he has done in this universe". The guard narrowed his eyes at her and almost studied her as she stood from the ground.

"You do not defend yourself?" he asked, not retorting her statement. "I would have thought that, with such a reputation as yours, you would defend yourself first".

"I've accepted my fate. I know that I will be feared wherever I go. That's the thing about my... Condition. You don't need to build a reputation, you have one from the moment you step onto a planet", Missy lulled, losing herself for a moment to nostalgia. He was buying time. Waiting for something. Someone. "So what is this? Who are we waiting for?" Missy started to walk through the door, but was pushed back roughly by the guard, who immediately blocked it with his spear. "You'll regret that", she murmured to him, dusting off her skirt.

"You won't live to carry out your threats, Time Lord, so don't make them. Though, that's you, isn't it? All bark but no bite". He was toying with her. Like a cat digging its claws into its prey just enough for it to bleed, but not completely pass. But she wasn't going to take it.

"You know what, I think I'll take back what I said about tearing this organisation apart", she commented with a maleficent smile painted across her face. "That's too easy. And too boring. Hate being predictable, especially when it comes to such simple minds. That's my favourite thing - outwitting a great fighter. Because they always think in black and white, 'This person will do this and this person will do this'. Never very imaginative, are you? Never think just outside the boundaries of the comfortable little box you fit your thoughts into. So, no, I won't kill you. In fact, I think leaving you alive would be more painful than any torture I could give you. I'm going to track down the next generation of the Heriotza and bathe the Shadow Proclamation in their blood. But I'll leave you alive. Because your children will be the first to go, then you can explain why your comrades' offspring are all dead because of you. That is my bargain, you stupid boy". Missy took a breath, her eyes burning with rage. God, that felt good. That felt... Like the old days, the better days. Empathy and compassion had flew out the window and, though she immediately blamed it all on the guard blaspheming The Doctor, it was all just to feel the sweet taste of evil again. It was all to feed her addiction to the dark.

The guard looked on in horror, at first, then his face twisted into anger. "Monster" he whispered, his face twitching. His fists were curled tightly and he looked down at the ground in an attempt to calm down. Obviously Missy's threats had certainly hit home. "I promised I wouldn't hurt you before they took you to your execution. They said it would disrupt how the machine worked". Taking a moment, Missy ran her eyes over the guard, noticing bloody streaks along his knuckles and under his fingernails. The wounds looked old, but hadn't properly closed. So, history of violence. Missy supposed that was the only thing needed to be a Heriotza Guard, though this one did get wound up easily in her opinion.

"You wouldn't do it anyway, dear. You've been threatening me for the last half an hour and yet I still stand here", Missy lulled, turning to face the wall. "I don't think I am the one that is 'No bite', I believe that title goes to y-". She spun around just in time for the guard's fist to connect to her cheek, making her stagger to the ground with pure shock. Looking at the guard through glazed eyes, she flashed an insane smile and put a hand to her split lip. "I stand corrected", she said in a low voice, biting her lip so that blood filled her mouth. "God, you are a fiesty one. You don't like me mentioning your kids, do you?"

"Just like you don't like me mentioning your precious Doctor", the guard retorted and walked away. His last mistake. "I don't have children, but I put my comrades first, and I wouldn't let anything happen to them. Especially at your hands. They deserve a much more honourable death". That was the last straw for Missy. Kicking out her leg, she twisted her shoe around his ankle and pulled, toppling him to the floor. Taking her hair pin out of her hair, she flicked it to reveal a needle-like blade. Attacking the face-down guard like a lioness, she landed on his back so that he couldn't move and landed the blade in the soft groove at the back of his neck, twisting it until the guard stopped struggling.

"Shit", she said quietly, pulling the blade out with a crack. "This really isn't going well, is it?"

"Maybe you should just stay with me", sounded the Master's voice in his head. "I mean you're awfully good at it. It's good to know I haven't... Lost my touch".

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"Death is an increasing problem. With over a billion intelligent species active in this galaxy alone, it is an ever-greater challenge to know how to kill all of them. On this planet, we are proud to serve as executioners to every living thing", Rafando pronounced, standing at the front of the boat that moved swiftly through the teal waters of the river. Standing beside him, The Doctor didn't look towards him, just stared off into the distance, wondering where they were holding Missy. Wondering whether she was okay. "The destruction of a Time Lord, however, is a particular honour".
Docking the boat at the edge of a stone dais with a platform in the middle, The Doctor and the Heriotza that escorted him hopped off. Four columns stood at the corners, with copper spheres at the top. The Doctor recognised it - only a few days ago he was tearing the wires out of it. Rafando continued speaking as The Doctor examined the machine. "This better work", he thought to himself. Though some may call him selfish for continuing Missy's destruction of the galaxy, he couldn't let her go. Not after all this time. Not after everything they had been through.
"This technology is precisely calibrated. As you can see, it will stop both hearts, all three brain stems, and deliver a cellular shock wave that will permanently disable regenerative ability".

"I know how it works", The Doctor retorted.

"You certainly will in a moment", Rafando answered quickly, with a smile which only made The Doctor's mood worse. How they could find pleasure in this was beyond him? Though, he did feel like a hypocrite when he was freeing the one person who could empathise with the idea. "Following termination, the body will be placed in a Quantum Fold chamber, under constant guard for no less than a thousand years. In case of, shall we say, relapses. Life can be a cunning enemy. An additional stipulation of the Fatality Index is that the sentence must be carried out by another Time Lord. Apologies for our choice, but your people are not easy to come by". A door creaked behind him and he turned to see her, all dressed in purple and black. His friend. His Missy.

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He looked older, slightly rougher around the edges. It had been a while since she had seen him last. God, he needed a haircut. His silvery curls seemed more unruly than ever, reaching out from his face like waves. Though she couldn't really say much, with her beehive hairdo that domed upwards to quite an impressive height. She would have thought that perhaps River would have done something about it, though, if you were on borrowed time, would you really stop to think about haircuts? River. His wife. It still didn't quite seem right that her friend was married. To a human of all creatures! Well, half-human, half-Time Lord, but it didn't count. Though she had tried marriage before, it never seemed to quite stick. Well, what could she say? Lucy Saxon tarnished the idea.

"Oh! Doctor! I didn't expect you. Thought you'd retired. Domestic bliss on Da-rill-i-um, that's the word among the Daleks. What happened?" Missy lilted, meandering her way towards The Doctor, closely followed by two guards. His face was a picture of sadness. Of regret. Of grief. It didn't take Missy too long to figure out what had happened. Her voice lowered, to show her respect. "Oh, I see. My condolences". Though she obviously felt her friend's loss, she couldn't help feeling a touch of happiness at being his only suitor. The last one standing. The Mistress outlived the wife, so, perhaps she could give him a shoulder to cry on. Or more.
No, enough of that. They were friends, nothing more. She couldn't keep thinking about what could have been. Because that was in the past and they both had changed since then. She gestured towards the dais and The Doctor walked alongside the lake, a sullen expression on his face.

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He didn't want their meeting to go like this. He didn't want... This. This felt wrong. And even though he knew that the machine wouldn't be lethal, what if it did something else? It was technology he didn't know of, advanced technology. What if he had made it worse? It was never good to mess with elements one didn't know about. A wave of panic rushed over him for a second. He couldn't lose her. All those days waiting on Gallifrey for her, thinking she was dead, he couldn't do that. And knowing that she was dead, that he could never hear her laugh again, or talk about the old days, made a horrible feeling rise through him.
"The prisoner will kneel", Rafando commanded, but Missy didn't move, just tilting her head, as if to say 'Make me'. She was always the stubborn type. Rafando nodded to the two guards behind her, who took her by the arms and up the steps to the platform.

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"Right", she murmured and lifted her skirt to reveal a white underskirt and black boots with thick chains across the front. "Thank you". She knelt onto the dais and looked ahead, feeling The Doctor's eyes burn into her head. She felt awful about leaving him on Gallifrey, and she really didn't have an excuse. Lying low was her main objective and she hadn't really thought about anything else. The Heriotza was on her tail and she didn't want The Doctor caught in the crossfire. She didn't want The Doctor caught in anything, but here they were.

An awful clanking sound echoed from the lake and four pulleys started reeling in thick chains from the water. A large cube, decorated in spiked circles, rose from the depths, water spilling off its metallic sides. "My final resting place", Missy thought. "How wonderful..."

"The Quantum Fold chamber is prepared", Rafando exclaimed and eyed Missy with a humoured gaze.

"Great", she replied sarcastically. This was how she was to die? Not in gunfire or flame? But dying at the hand of her only friend. The only one who bothered to see past her madness . When she set out, exploring, destroying or ruling the galaxies, she never saw her end as this. To have a death that was so... Boring.

"The sentence will be carried out. Executioner?" Rafando barked at The Doctor. Missy looked straight across at him, as he was told and moved to face her, taking in his hand a long, golden lever.

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He couldn't look at her. Couldn't see those sad, blue eyes which tore holes in his heart everytime they looked at him. He could only wonder what emotion they held: rage, betrayal, sorrow.

"Please", she murmured, in a small voice. "I'll do anything". Reluctantly he looked up to see her and scanned her face. Was that fear darting across her eyes? Was she actually... Scared of dying? A long cut ran down her lip, which only made The Doctor wonder what scrapes she had got herself into this time, or what conditions they had kept her in. "Just let me live". The Doctor's face fell as he tightened his grip around the lever. His hearts ached with the thought of her. He was vain and he was a sentimental fool. While he was saving himself from having to deal with another loss, he was unleashing Missy back on the universe again. But he couldn't keep losing people. He just couldn't. After River, he knew that losing Missy would just break him. He had done so much for the universe, it was about time it repaid him.
Tearing his eyes away from Missy for a moment, he saw a hooded figure approaching the dais, unlike any of the Heriotza.

"Have you requested a priest?" Rafando asked, puzzled.

"Well, I haven't", Missy commented. The Doctor silently laughed. What use would a priest be to Missy? She'd be in confession for longer than him and he refused the Pope because it would take too long.
A hand reached out of the navy robe to gesture The Doctor forward.

"Apparently I have", he murmured and started to walk towards the figure.

"I shall seek consultation", Rafando answered, stopping him in his tracks and twisting the device on his wrist, which trilled and tapped. Missy rolled her eyes, sighing and sitting back on her heels. Was killing her really going to take this long? She couldn't remember dying taking this long for her other regenerations, though, if she was perfectly honest, she couldn't exactly remember her other regenerations.

"There are four hundred and twelve precedents in the Fatality Index. Divine intervention, therefore, is permitted for a maximum of five minutes", Rafando explained, looking quite proud at himself.

"Five minutes", Missy echoed, disbelieving. "I'll just do it myself, might be quicker", she thought.

"The executioner may now discuss his immortal soul and any peril thereunto", Rafando announced to the attendants of the execution and The Doctor walked over to the cowled figure, his eyebrows furrowed into confusion.

"Greetings, sinner", the creature spoke in a theatrical tone. "Only in darkness are we revealed".

"I never sent for you".

"Goodness is not goodness that seeks advantage. Good is good in the final hour, in the deepest pit without hope, without witness, without reward. Virtue is only virtue in extremis. This is what he believes, and this is the reason above all, I love him. My husband. My madman in a box. My Doctor". The Doctor took his hand off the page and the figure closed the book that he held in his hand, holding it close to his chest to reveal its cover. Deep blue, with rectangle embossings, to match his TARDIS - River's diary. As if Missy wasn't enough to break his hearts, this figure had to throw River Song into the mix as well. He pulled the hood from his head to reveal Nardole, with a small grin on his face.

"Your missus wouldn't approve", Nardole murmured. The Doctor thought otherwise. He was sure she would be quite happy to get rid of a contender for The Doctor's affections.

"How the hell did you get here?" The Doctor hissed. He believed that, after rebuilding him, he would just leave him to his grieving, not follow him across the galaxy.

"Followed you from Darillium, on the explicit orders of your late wife, River Song. Warning, I have full permission to kick your arse". The Doctor nodded slightly. He didn't doubt his wife's requests, nor Nardole's ability to do such a thing, especially with his... Upgrades. Looking back over to Missy, he had a very sudden feeling of déjà vu - he was caught in between his Mistress and his wife again.