"Jim, you really don't have to do this." Sherlock's voice was steady and firm. If he could just convince Jim to let the girl go...
"Oh, Sherlock." Jim responded with a chuckle, "you disappoint me. I thought you might have enjoyed our little 'diversion'. Changing things up a little. You know, variety is the spice of life and all that."
"Just let the girl go, Jim. Please." Sherlock's voice was raised; desperate. He tried to reign it in, but the whole situation was beginning to make him panic. "I'll do whatever you want. You know that. Just... please... let Chrissie go. She's just a kid."
Jim sighed and walked towards Sherlock, placing a hand in his hair and stroking it almost fondly.
"Sherlock." he began, his voice calm, as if talking to a small child, "I know you will do whatever you need to do. And you can help this girl, don't worry. For every thing that you do for me, it is one less bad thing that can happen to dear little Chrissie here."
Chrissie let out a strangled yelp at the same time as Jim pulled hard on Sherlock's hair, yanking his head back and drawing tears from his sensitive eyes. Sherlock presumed that perhaps "Sebby" was doing the same to Chrissie - to make the point.
Jim roughly dropped Sherlock's head and leant down to whisper in his ear.
"It's all up to you, Sherlock. Either you take it or she does." He finished up by inhaling Sherlock's scent deeply. The scent of fear; of anticipation; of... Sherlock.
Sherlock wondered for a moment about the point of all this. Jim knew that Sherlock would do whatever he needed to anyway, so why involve the girl? This was Jim Moriarty though. Jim was in it all for the game, and he would know that the involvement of a third (or, in this case, a fourth) party would affect Sherlock. Unfortunately for Sherlock - and for Chrissie - Jim Moriarty knew the Holmes brothers far too well.
Sherlock heard the Irishman walk away, and he was again aware of the two men's muffled voices as they spoke in the adjoining room.
Chrissie had started sobbing again, her breath jerky as she tried to bring it under control. After a moment of feeling annoyed at her presence and involvement, Sherlock realised that he needed to reassure her somehow.
"Chrissie?" he began, his voice hushed and low, "Chrissie... listen to me. I will not let anything bad happen to you, OK? Do you hear me?"
Chrissie went quiet for a minute before responding. "But... but why would you do that? He will hurt you." Sherlock could hear the concern and fear in her voice. She was torn between her desire to be safe and worry for Sherlock.
"It's OK, Chrissie. He will hurt me anyway." That much was a given, and Sherlock tried to keep the resignation from coming across in his tone. "But he doesn't have to hurt you too. I will protect you from it as best I can, OK?"
The detective was tempted to open his eyes and assess the situation. It was clearly getting out of control. Nothing good was going to happen here, not with a young, innocent teenager here and Jim and whoever Sebby was.
He resisted the urge to look, knowing he would only cause himself greater discomfort, instead withdrawing into himself for a moment.
Think, Sherlock, think rationally, he told himself.
Jim had a hold over Sherlock and Mycroft - How?
Because he knew that Sherlock had killed his father - albeit in self-defence and defence of his brother.
Because he knew that Sherlock and Mycroft had been involved in an incestuous relationship.
Because he had benefited from Mycroft's assistance in making many crimes and situations "vanish" over the past 10 years.
Sherlock paused a moment, processing that information. What proof could Jim have? It'd been ten years since Siger Holmes died. It was a closed case. Even if it was re-opened again, could Jim really have any solid evidence that it was anything other than an accident? Could there really be any proof of Sherlock and Mycroft's relationship? He was fairly certain that Mycroft would not be so stupid as to leave any sort of paper trail regarding the covering up he had done.
Sherlock began to chuckle. It was as if the weight of the world had been lifted from his shoulders, and suddenly, he saw everything with perfect clarity.
The Holmes brothers had been so broken when Jim first revealed himself to them, that they had been blind to the obvious.
He had nothing.
Absolutely nothing.
Sherlock stifled the chuckle, hoping it hadn't drawn too much attention to himself, and began to work through the finer details of what he needed to do next.