Betrayed (Warnings: Betrayal!) -

Isabelle relished the look on his face as soon as she entered his home office room without knocking. The knot that formed between his eyebrows, the silent question in his grey eyes. Isabelle had always respected his privacy, it must be important if she ignored that. And it was important of course, just not in the way he was expecting.
"Is there something you need My Dear?" he asked in a voice as smooth as silk. Isabelle smirked, approaching his desk and stopping right in front of it, roughly shoving aside the wooden chair meant for "guests". Her husband raised an eyebrow at her, saying nothing. She allowed him to take in her appearance, a low cut grey shirt, skinny jeans, her hair tied high up on the back of her neck. All of these were unusual, but his gaze lingered on the purse hanging over her thin shoulder. Isabelle brought a hand up and tugged at the zipper keeping the bag closed, shoving her hand inside and fingering the object within. "There are a few things I'm going to need of you, Myc," she sneered. His shoulders stiffened, a thinning of his lips and his eyes narrowed slightly. Still there was familiarity and trust, which amused Isabelle even further. He thought she was upset over something trivial, silly Isabelle.

Mycroft shifted his comfortable office chair backwards and looked ready to stand up and confront her in a manner he knew his wife would prefer. Isabelle stopped him with a snarl, bringing out the object her bag had so nicely hidden. "Stay," she instructed harshly, smoothing out her features to something less sinister. Mycroft hesitated, his mouth opening a fraction in surprise and confusion. "Isabelle-" he said, then stopped. The gun was nothing special, a small black pistol that was of little use unless she wanted to shoot from close quarters. But that was the intention. "Surprised?" Isabelle nearly laughed at his expression, she'd been waiting for this for five long years. He knew the weapon was real, he was after all, vastly intelligent. Still there was a sense of disbelief that colored the following sentence, "Isabelle, what are you doing?"

Isabelle looked about the room for a moment then down to her gun, shrugging. "I would have thought it obvious," she hummed, mocking many a similar time he'd said that. Mycroft remained silent after that, leaning back in his chair. Isabelle decided to fill the gap, "I must say it took me a long time to get to this point, but it was worth it. All of those times I had to pretend to be a pathetic mummy's girl that cried at a drop of a hat? Every time I had to sell my emotional abuse, the desperation! God, it makes me sick just thinking of it," she raised the gun a fraction, considering shooting him in the head… or even better, his heart, she did love irony after all.

"Isabelle... has someone coerced you into this situation?"

Oh that was adorable, poor baby. Isabelle shook her head gently, "I was hired quite some time ago. See, that's the thing about you Myc," she stepped forwards once more, "From your file I knew I had to play someone helpless, imperfect, emotional. I knew you would be drawn to ikkle Izzykins right away as soon as you deduced the relationship with her sisters and when you made her cry? Gold."
Mycroft shook his head, "You cannot convince me that these past years have all been a lie I-"
"Can't I?" Isabelle cut him off, the following audible click filled the room with her husband's tension. He was afraid just then, she could see it. His suddenly cold expression had faltered, a twitch of his lip, tension in his shoulders and hands. "Isabelle, if that is indeed your real name," he tilted his head to the right a fraction, "If you go through with this, you will not leave the building alive. I have security-"
"You don't get it!" Isabelle's shout rang through the enclosed space, "I'm Isabelle, your lovely wife! They won't stop me from leaving here, they won't have a clue! No one searches me when I come back here or when I leave, I'm safe. The only woman Mycroft Holmes allowed himself to get close to." He loved her. Mycroft swallowed, "Clever," he conceded plainly, hiding behind the mask. It'd taken some finagling on her part to get through that icy exterior, but she'd been patient. Her ability to play the waiting game had been the main reason anyone ever hired her.

Long pale fingers threaded together in front of the man's golden pocket watch, "Well, I suppose if you must, there is little I can do." Mycroft sounded as though the whole thing was an inconvenience, putting on a brave front, not wanting to give her the satisfaction of seeing him afraid. Isabelle allowed herself one moment of sadness, a brilliant life was about to be snuffed out. Over the years, while she hadn't allowed herself to love him, she had come to admire what he was and what he stood for. Mycroft Holmes the eternally dedicated. It was a shame, but that wasn't going to stop her. "Any last words?" She prodded, running a hand over her long chestnut braid. She was going to celebrate being able to wear her hair short again!

Mycroft shrugged, "I suppose there are a few things I would like to say. I won't of course, there is little point. Why attempt to endear myself to my killer?" he hummed, "Though perhaps, if you could make it...quick?"

Her heart twinged.

Isabelle hands sweat, though she nodded once, resolutely, "Whatever Myc, I don't care either way. If you're ready?" she readied herself, using both hands to steadily grip the weapon in her hand.

She fired.

April 1st! I couldn't help it. Sorry guys. Of course I admit the idea of anyone pulling all of that off is a bit ridiculous!

Next chapter is still being worked on and will be an actual "How they met" AU scenario. ;)