Lestrade cleared his throat before he spoke."There is no John Watson. There never has been."
Sherlock froze. "What are you talking about?"
"Look him up. There are a dozen John Watsons, but none are the one you know. What is he, a war hero with a psychosomatic limp? He never existed."
Sherlock frowned, and turned to face John, who had remained in the corner.
"John, you'd better explain, because I am not getting this."
John only looked back blankly. Clearly he was no more informed than Sherlock was.
Lestrade was looking at him sadly. "There is no one there Sherlock. You invented him."
"Invented him?"
"Mmm hmm. Invented the flatmate who came to stay with you, the one who supposedly shot the cabbie you were matching wits with, honestly, that was a pain."
"Oh, don't be ridiculous!" Sherlock scoffed.
Lestrade sighed. "Can you honestly tell me you are absolutely sure that man exists?" he asked, gesturing in the general direction of John.
"Look, for god's sake, this man was a war hero!"
Lestrade shook his head. "No Sherlock. He wasn't. The unit he was supposedly in, Fifth Northumberland Fusiliers, they didn't exist."
Sherlock looked at John, who only shook his head angrily before walking out.
"But... then who are you? What about Mrs Hudson? Surely she knew that I had a flatmate," Sherlock noted smugly.
Lestrade looked up at him. "I'm your therapist," he said slowly, as if Sherlock was an idiot. "But you seem convinced I was a Detective Inspector. I went along with it, because I hoped it would allow me to get closer to you, but it really didn't help." He shook his head. "And as for Mrs Hudson, she's a nurse. She makes sure you're safe at home."
"Stop it. Stop it now!" Sherlock shouted. He glared at Lestrade.
"I'd like to go home now," he snapped.
Lestrade nodded at the woman who had no name.
She accompanied him in the car.