"You must promise me, no matter how bad things get, you will not reveal to anyone what we've done."
There is an adamant note in Sherlock's voice that forces Molly to glance up sharply. She is tired. She was before this hellish nightmare began, and now, when things are at their worst, she wonders from where she will draw the strength to carry on.
She looks up into Sherlock's eyes and sees he is no happier about what he is asking than she is. That makes her feel slightly better, but not much. What he is asking of her isn't just cruel, it's – Even in her thoughts, words fail her. She knows he is serious. Serious as the grave, because he already swore her to secrecy before he took her into his confidence.
And if she is tired, she knows he must be exhausted. Sherlock's been on the run since escaping police custody, and it's possible that the strain has been too much. Maybe he's talked himself into this as the easiest way out. Maybe he just can't see another path.
His scheme, the one in which she has volunteered to be his willing accomplice, is spectacular in its audaciousness. She's watched behind the scenes features on action film DVDs where they've done similar stunts, and even with all of the safety gear and practice, it was still risky business. With what Sherlock was proposing, no harnesses or safety lines, the timing had to be perfect or the theatrical display he intended to perform would become reality instead of just a grisly illusion.
Bearing that in mind, Molly had made him step through every aspect of the elaborate hoax a second time, partly to answer specific questions, and partly to force Sherlock to pick the details apart to expose any flaws. There would be no dress rehearsal, no second chance. Everything had to be perfect. It took almost an hour, but finally they were both satisfied.
"Why?" she asks, although she suspects she knows. "This is going to devastate him." To save Sherlock a little pain Molly doesn't say his name, but she doesn't have to. John Watson is never far from Sherlock's thoughts. To keep him in the dark when they could spare his feelings seems incomprehensible.
Sherlock looks away, and the anguish that etches his face into haggard lines makes it obvious he knows exactly how horrible a promise this is. "I'm doing this to save him." He sighs and makes a visible effort to gather himself. "You know how the media works, Molly. They'll be on him 24/7. John isn't capable of lying convincingly under that sort of pressure. And it's vital, for his safety as well as mine, that he be believed."
"Are you sure there's no other way?" It's not the first time she's asked the question. The first time she'd done so the impossibility of the situation demanded it. Now she repeats the query because while her doubts have been laid to rest about the plan as a whole, for this aspect of it she wants another solution.
Sherlock smiles at her, and it's poignant. He understands that to spare John Watson is to spare his own heartache, and that is what Molly wants most of all.
"I promise you, Molly, there's not. For the moment, Moriarty has bested me. I regret the theatrics as much as you, but in this instance we must give the public what they want. John will be the perfect Chief Mourner."
It is her turn to sigh. The public, once his biggest fan club, is now baying for Sherlock's blood. From the moment Sherlock turned up and made his softly spoken confession that he feared he was going to die, they had been building towards this moment. He trusted her enough to share his troubles. He trusted her enough to enlist her help in carrying off his audacious plan. He trusted her enough to play her part in its miserable aftermath.
She still hasn't given him her word, and she knows Sherlock is on the verge of asking again. "If I do agree – " She's stalling for time, trying to find a way out of this madness, but Molly suspects even if she were fed and rested she'd be out of her depths. This is a chess game being played on an epic scale. She's always been hopeless at chess, still it's not lost on her that in this gambit she is a pawn promoted to knight and Dr Watson is the queen. Using him so coldly is not capricious nor maliciously intended, but necessary if Sherlock is to win. Despite her rationalisation, a shiver runs down her spine at the callousness of the mind who could devise such a stratagem. "– will you promise me something in return?" Molly has no right to ask. On two separate occasions she has offered Sherlock her unconditional support, but on his behalf, she does ask.
The look in his eyes says that Sherlock knows what she wants. "I promise you. When this is over, I will do all I can to make amends."
It's not much of a promise, but under the circumstances, it's the best she can do for the both of them. "Then I agree."
"Molly." He has already asked everything of her, and yet Sherlock has another request. She looks up at him in time to see his mouth open and close, as if he is hesitating over his words. "If it's not too much to ask, be a friend to him."
She nods, one quick bob of her head, and then wonders how she will fulfil her role as Sherlock's secret keeper when faced with Dr Watson's grief. He's knowingly putting her in an untenable position, and yet he trusts her enough to ask this of her.
"Thank you."
Such simple words, and this time, they are freely given. She swallows hard over the sudden lump in her throat, and for a moment Molly is afraid she might cry.