Please note: contains slight spoilers for LADY.

For all his remarkable powers of observation and deduction, Sherlock Holmes didn't realize he'd made a massive miscalculation until he saw that the man's hands were wrapped tightly around Watson's throat. He rose to his feet quickly, looking around for something to defend Watson with and wondering how he'd let this happen.

He should have foreseen this, shouldn't have sent Watson to investigate on his own. Watson, he was certain, had done as he thought best, but he shouldn't have expected him to be a detective. That had never been Watson's role in their partnership, nor had Holmes expected it to be, though he often challenged Watson to grow his grasp of the art of detection. Watson never failed to accept Holmes' challenges, even taking on the observational challenges of his own accord. Holmes was always delighted when Watson was able to offer him an interpretation of facts which was very close to being correct, for it boosted his faith in the idea that one day even the most ordinary men could be able to curb crime in the world by simply observing their surroundings. In addition, Watson's observations about a case were often more than ample to put him on the right track if he faltered. To hear the conclusions of someone who had seen, but not observed, all the evidence, was invaluable.

Holmes had not hesitated in sending Watson on this case. He had absolute faith in Watson; his loyalty, honor, and steadfastness were beyond doubt. Holmes realized, however, in the moment he saw Watson being pounced upon, that he really should have doubted his friend after all. He should have doubted that Watson would be an unobtrusive observer, that he wouldn't take the case personally, and that he'd use a soft touch when confronting the unknown.

As a doctor, Watson was quite used to handling situations with delicacy, but as a detective it was a different story. Watson was usually insistent and direct, and that was certainly the line he'd taken now. It had been the wrong play, and his poor throat was suffering for it.

Holmes had moved hardly without knowing it, brandishing a large stick as a cudgel and striking Watson's attacker on the arm. Holmes knew who he was, of course, but Green didn't recognize him. He looked in between Holmes and Watson for a moment while Watson reeled, trying to catch his breath. Green almost renewed his attack, but Holmes snarled at him, and he backed off.

Holmes watched as Watson struggled to right himself. Polite as ever, Watson thanked him in his best French, but all Holmes could do was frown darkly.

"Well, Watson," he said, "a very pretty hash you have made of it! I rather think you had better come back with me to London by the night express."

Watson's face fell, but Holmes couldn't bring himself to offer the doctor any comfort. The case was bungled, and Watson's actions had set them back.

Watson opened his mouth as if to say something, but Holmes shut him up with a look. He didn't want to talk about it, not yet. He turned, knowing Watson would follow him. After a moment, though, he turned back, realizing Watson had stumbled. He didn't care that Watson waved him off, he took Watson's arm and walked with him back to the hotel. "Go to your room," he said. "I'll join you there." He didn't intend to sound like a disapproving parent, but the tone leaked into his voice anyway.

Watson didn't look at him, meekly doing as he said. Holmes gathered his own things, changed quickly, ordered tea to Watson's room, and sent word to Green before going back to Watson. He entered without knocking, catching Watson grimacing in pain as he rubbed his neck. He frowned, sighing.

"I thought so," he murmured. "Can you speak?"

Watson shrugged. "I feel worse at heart," he rasped.

Holmes nodded. "Sit down, my friend, and I will tell you how I happened to be at your service when you needed me. I suppose you think I am some kind of magician, but I assure you the explanation is very simple. Ah, here's a cream which will soothe. Undo your collar, man, and let me see what has become of you. I suppose it is only fair that I play doctor, since I recklessly sent you out to play detective."

Watson didn't answer, looking away with a mix of shame and embarrassment as he bared his throat. Holmes couldn't help being a bit taken aback at the damage.

"My dear man! I had no idea the attack was such a savage one! Can you breathe easily?" he asked.

"I'll live," Watson rasped, still sulking.

Holmes sighed. "Hold still." He tried to be gentle as he tended to the angry red marks on Watson's throat, some of which were, already, turning a dark black. Green had dug his nails in as well, causing Holmes to need to swab away the blood and Watson to need to change his shirt.

Watson said nothing as Holmes explained himself, but Holmes could already tell that his lips and tongue were swollen: Green must have been a ferocious attacker indeed. The tea Holmes ordered arrived, and Watson drank it very slowly, unable to hide how he was having trouble swallowing.

"I am no great doctor as you are," Holmes said, "and you are no great detective. It has been a complicated case."

"I have investigated as I thought you would ask of me," Watson said softly.

"And a singularly consistent investigation you have made, my dear Watson," replied Holmes. "I cannot at the moment recall any possible blunder which you have omitted. The total effect of your proceedings has been to give the alarm everywhere and yet to discover nothing."

"Perhaps you would have done no better," Watson answered, and he didn't try to hide the bitterness in his voice.

"There is no 'perhaps' about it," Holmes replied. "I have done better." He didn't like that Watson was sore at him, but he wasn't sorry, for his words were true. Besides, he was a bit sore at Watson, too. Nevertheless, he reached out and touched Watson's arm. "All will be made clearer soon."

"Holmes," Watson murmured. "I apologize. I should have simply done as I was told."

Holmes 'tsked' with his tongue, not liking the idea of Watson as a subservient automaton even more than he didn't like getting the results he was looking for while on a case. Watson didn't seem to notice, but he did sense the shift in his friend's mood, finally looking at Holmes. "And I apologize, Watson," Holmes said sincerely, finally feeling released from his frustration with his friend. "I never imagined you would be harmed."

Watson nodded, though even that made him grimace.

There was noise from outside the room. "Here is the Honorable Philip Green, who is a fellow-lodger with you in this hotel," Holmes said with a smile, "and we may find in him the starting-point for a more successful investigation."

Watson gave him a look that clearly said he would happily do anything if it meant a more successful investigation, which was just as well, for a very different look indeed came over his features when saw that Holmes had invited his old attacker into the room.

For the prompt from sirensbane: Role reversal.

For anyone familiar with the show, spot the "Sherlock Holmes in the 22nd Century" reference, put there just for fun :)