"What are you doing?"

Sherlock looked up from his violin, eyebrow raised.

"I'm playing the violin, obviously."

"No. With your face. What are you doing with your face?"

"I'm smiling, John. It's what you said normal people do when they enjoy something."

"This doesn't look like a smile."

" . . . This is a smile."

"You look like you're in pain, stop it."

"I'm not. I think I would be smart enough to help attend to whatever wound."

"I don't think you get what I mean. Just don't do that in public, they'll think you're hurt."

"Who said I would smile in public?"