"Then what happened?" John asked. They were sitting at the kitchen table, drinking tea that Sherlock – that is, Orlonamaorlion - had made.
"I became human," Orlonamaorlion said. There wasn't the slightest degree of condescension in his deep voice.
"It's called a Chameleon Arch. It rewrites your genes – very painfully - stores your memories in one of these fob-watch-like containers and it simultaneously implants whatever cover story you've concocted beforehand. When you open it, it reverses your genetic rewrite and restores your memories." He sat back and smiled. "I had developed it before I went to Earth. I came here – this world, this time - and tested it. Apparently it worked."
"And your cover story is that you were a genius consulting detective who was purely rational and didn't like women."
"Something like that."
"Because you wanted to stay faithful to your late wife and not feel any emotion whatsoever."
The naked expression of grief on Sherlock's face was startling. "You're probably right, John."
"But then what about Mycroft?" John asked hastily.
"What about him?"
"Is he a – a what do you call it, a Gallifreyan too?"
Orlonamaorlion just smiled. "What do you think, John?"
The two sat drinking tea and staring into various distances. "So …" John finally said.
"What happens to you now? Do you just zoom back to your home world?"
"No, John, not until the Doctor comes back. And he will. I promise you he will."
"Well, he'll need to refuel," Orlonamaorlion said. "And while he's here, he'll want to see if I did take the hint and open the watch. And when he does, I'll have a lot of explaining to do."
"How do you mean?"
"Well, I abandoned him when he was four, he's going to want to know why." And in another un-Sherlockian gesture, Orlonamaorlion sighed and ran his hands down his face. "That's a conversation I'm not looking forward to having with the boy."
"That man – the Doctor – is your son?"
Orlonamaorlion smiled. "Didn't you notice the cheek bones?"