Moriarty
"Sherlock! What is going on?" John demanded as the two men clambered into a cab.
"This location," Sherlock told the cabbie, holding his phone forward with what John guessed was an address displayed on the screen. The cabbie pulled away from the curb and drove off. Sherlock passed the phone to John.
"The pool! Why..." He glanced at the message above the address, then at the initials below it. "You got a text from somebody using Moriarty's initials saying to meet him by the pool." He turned to look at his friend, aghast. "You seriously think this is safe!?"
"Of course I don't, John. It's obviously a trap."
"And you're still going."
"Nothing we do is safe. This may be our chance to find out what's going on."
"Of course," John muttered. He leaned back in his seat. Sherlock seemed totally unfazed by the potential danger, but he couldn't shake the feeling that something truly bad was going to happen.
The pool was dark and silent when they arrived. Sherlock entered first with John close behind, their footsteps echoing in the near empty space. John began to wonder if it was all just a joke. There was no one there. Suddenly, the lights flickered on as a familiar character entered dramatically through the opposite door. "Sherlock! How pleasant to see you alive!" he said loudly, making wide gestures with his hands.
"And you as well," Sherlock said simply. John half expected to hear the note of arrogance in his voice that showed that he had known the truth all along, but the detective seemed just as surprised as he was.
"I knew you'd come. You couldn't resist an answer, could you?"
"A bullet went through your head. I saw you up close. You were dead." John could tell the Sherlock was searching for an answer he couldn't find, just had he had done dozens of times before. "How did you do it?"
A red dot appeared on Sherlock's forehead and, judging by the way his friend turned to look at him, there was one on his own as well. "You first," hissed Moriarty. "Your boyfriend's alive – you must have jumped! That should have been the end! But YOU CAME BACK! YOU CLEARED YOU NAME! HOW?" He paused. "I heard that fool Anderson's theories! But none of them were CORRECT, WERE THEY? HOW DID YOU DO IT!?"
"I'm going to tell you and you're going to let us walk away?"
"No! You're going to tell me and you are going to die! FOR GOOD! I am going to watch you DIE!"
"Seeing as I'll die either way, it would be easier not to tell you." Sherlock sounded cocky, but John could tell he was scared.
Moriarty clearly saw the flaw in his own plan, but his eyes quickly flicked to John. It was clear he had no real preference as to his fate. "You tell me, he lives!"
Sherlock looked at John, desperate. He was obviously trying to think of some option, and John saw glaze slightly as he tried to enter his mind palace. But he needed time for that and time was something they didn't have. "John, go."
"No."
"NO! He stays until you tell me! EVERYTHING!"
Sherlock told him. His voice was cold. The glee John would have expected as he told Moriarty how he had outsmarted him was not there. He finished "Now, John," he said, almost as a conclusion to his tale.
"Sherlock, I'm not leaving you here."
"John, go. Now."
"Sherlock..."
"John. You have a son. Go." His voice nearly caught.
John knew he was right. He was a father. He couldn't choose Sherlock over his own son. He took a last look at his friend, then he turned and ran. Out in the hallway he heard the loud noise of a gunshot. He tried to keep himself from crying out.
Sherlock had turned out to be alive on more evidence than that. But this time it was worse. This time he didn't know.