Sherlock had dropped in on Mycroft, with John in tow, when the pair got home from Dartmoor. Earlier on in the case, Sherlock might well have gone to his Pall Mall home to yell at him, for sending Lestrade to spy on them. As it turned out, he actually went to offer begrudging thanks for Mycroft getting them into Baskerville.
Anthea answered Mycroft's door for him, Mycroft himself was pouring over some extremely official looking documents in his study, when Sherlock and John joined him.
John expected indignant protests, given he was clearly busy with something not meant for civilian eyes. Mycroft didn't even try to shuffle the papers out of sight. Instead, he looked up, staring at Sherlock, an utterly peculiar expression crossing his face.
It obviously wrong-footed Sherlock too, as he stopped before he could even start mocking his brother in his customary means of sincerely thanking him. Mycroft was gazing at Sherlock as though he'd never seen him before in his life.
"What?" Sherlock asked, surprise removing any trace of scorn from his voice.
Mycroft seemed to realise he was acting strangely, as he blinked suddenly, bleary eyed as he stood up.
"Nothing, sorry…You escaped the Hound unharmed then?" He offered.
John and Sherlock exchanged a confused glance, before Sherlock shrugged.
"Yes. Your omnipotence was much appreciated."
Mycroft smiled faintly.
"And Henry Knight?"
"Has a good chance of finally moving on." John supplied, still utterly at a loss as to what on earth was wrong with Mycroft. His politician's mask had slipped back into place, but he was far from back to normal. He wasn't saying anything sarcastic or even…clever. He wasn't really saying anything at all.
"Good. Congratulations, Sherlock." He breezed, though his tone was forced. "My apologies, John, I didn't know his experiment would involve a human guinea pig."
John grinned at that, while Sherlock pouted.
"Yes, well, thank you Mycroft." Sherlock told him, adopting his theatrical, overly polite tone to remove the embarrassment of his gratitude. "We'll be going-"
"Sherlock-" Mycroft interrupted. A hint of the glazed look returned to his eyes. "If you have a minute, soon, I need to talk to you."
He didn't specify he needed to talk to Sherlock alone, but there could have been no other reason he didn't just say whatever he needed to say there and then. Sherlock studied him carefully, while Mycroft merely stared back at him, unblinking. Eventually, Sherlock nodded and left, John trailing after him, with a vague feeling of unease.
"What was all that about?" John asked Sherlock, as they headed back to Baker Street.
"I don't know." Sherlock replied, the displeasure in his voice matching John's uncertain feeling.
Sherlock didn't speak again until they were back inside their flat. He paused by the mantel piece, staring at his skull.
"Did you notice his hand?" He asked suddenly.
John wasn't sure what he meant for a moment.
"Mycroft's? No, why?" He questioned, confused.
"His left hand was bruised. He also flinched when Anthea brushed his arm…" Sherlock explained. He cocked his head to one side and looked over at John. "What would cause injuries like that?"
John's immediate thought was that as he didn't know what kind of injuries they were, he couldn't really say. Another diagnosis sprung to mind almost as quickly though, because this was Sherlock. While he didn't know much about medicine, there was nothing he didn't know about crime.
"Bruising to the hands, indicates a fight…bruising to the upper arms would be a sign of restraint. He was in a fight, someone stopped him?"
Sherlock nodded silently.
"He certainly hit someone hard enough to damage his hand. Whoever stopped him, needed to use enough force to bruise."
As Sherlock spoke, giving away no ideas he might have had, the way Mycroft had looked at Sherlock came back to John and a theory began to form in his own mind. He could think of only one person Mycroft would willingly get into a fight over. Mycroft had after all, almost allowed Irene Adler to 'bring Britain to it's knees', to cover Sherlock's blunder.
John wondered if the security breach at Baskerville had thrown up a problem for Mycroft. It was so unseemly to imagine him attacking anyone, let alone having to be forcefully dragged away. If it had happened, then it seemed most likely to have been in proximal defence of his little brother.
John suspected that saying any of this, would be something close to suicidal. Instead, he settled on a simple suggestion.
"Whatever it was, he said he needs to talk to you. I guess you'll find out."
