Robert sat up in bed. He wiped his eyes and put the phone closer to his ear. "Excuse me, Mr Holmes. I must have misheard you. Did you say that that I wasn't "allowed" to leave the country? What business of yours is it whether I accept a job or not?"

"It is my concern, because Sherlock is my business."

"The initial contract ends in a week. I am perfectly within my rights to take whatever appointment I wish after the term is over"

"No. Sherlock is doing wonderfully. He is back on track. He is studying music again. He has stopped drinking and smoking, and he has only run away from you once. This is working. You can not leave now."

"I can and I will."

"We'll see about that. Good Day, Dr Bell."

The phone clicked closed and Robert sighed. This was too much to take so early in the morning. He needed some tea. He rose heavily from the bed then, and wandered toward the kitchen, to find his living room completely covered with family photos. All of his photo albums had been torn completely apart. "Sherlock! What are you doing with my photographs? Those are mine, and they are important to me!"

Sherlock was on his hands and knees on the carpet. He sat down near a clump of grouped photos. "I wanted to find out about your past, so I looked at your photo albums. You never told me that you and your brother, Richard, were twins. And you certainly never told me that he was a murderer."

Robert stared at the young man and then crossed his arms. "Such a statement has no relevance without proof. You know my methods. Prove it."

Sherlock smiled then and pulled out a series of photographs of two boys and then men standing side by side. "You and your brother, always together, until University. Then we see you going separate paths: He, into business, you into science.

He pulled out photographs of Robert with a series of women. "You dated in University so did your brother. Since your parent's death, you have visited your sister Katherine's house for the holidays. But your work was always important to you. There is a case, or a bag, or a book related to your studies in virtually every picture that you are in. It is one of the best ways to distinguish you from your twin brother. That and the colors that you wear. From a young age, your mother dressed you in lighter clothes than your brother. The bright twin, and the dark twin. How prophetic.

"But these two pictures tell the real story. Here is your brother and a woman named Mary Ann Maxim. It says on the back Richard and his fiance. They are both happy and smiling. They show all of the signs of being in love. This is from the summer. But by Christmas we see a different story. She's no longer smiling. Instead of wearing reds and greens she wears black. She is actively leaning away from him. His hand is clutched around her wrist. His nails digging into her flesh. And this picture was taken on New Years Eve. Richard is alone. Strange for an engaged man to go alone to a new year's party. This is the last picture that you have of him. There is, however, this picture three months later of you and your sister at a funeral that must be Richard's."

"Yes. Richard died that spring. But you haven't mentioned a crime? What led you to believe that Richard was a murderer?"

"Mary Ann. The way that she looked at him, as if she was afraid of him. I just had a feeling."

"A feeling? Feelings are not admissible in court. Only the facts matter. What facts do you have to support your case?"

"You don't deny that your brother killed her. Are you admitting that it's true?"

"I admit nothing. The burden of proof is yours."

"Alright." Sherlock said rising and leaping around the pictures to the kitchen table where Robert's laptop was open. He turned the screen to face Robert. "I looked up Mary Ann Maxim and found that she had been murdered. The report is dated January third, but she died earlier than this, on new year's eve. She had been raped and strangled.

"Although Richard was originally suspected, later stories claimed that she was the victim of the Black Neck Killer. A serial killer who had claimed two victims before her. They were found naked, with black bags covering their heads and bruising on their necks from where they had been strangled."

"So far, your evidence shows that Richard was not the killer."

"Yes, but this is only what the paper says. I needed more direct data, so I looked into the police archives."

"How did you get access to the police archives?"

"I used Mycroft's security codes. There were no clear leads on the Black Neck killer, but Richard was the primary suspect in Mary Ann Maxim's death. She had told her friends that she was increasingly unhappy with Richard up to the day of her death."

"Couples have broken up before without murder being involved."

"Yes, but the testimony of her friends said that she was considering leaving him, but she was afraid to. The picture supports that claim."

"And the Black Neck Killer?"

"One of the detectives thought that it was Richard, but they didn't have enough evidence. His hands were about the size of those that made the bruises on the women, but so are thousands of men. Also, the bodies were found late, and the time of death was not specific enough to show that he was unaccounted for at those times. But Mary Ann's death happened on New Year's eve at about ten or eleven o'clock. If they could show that Richard killed her, they could also link him to the other killings."

"Why didn't they?"

"Because of this picture here, new year's eve. He was at a party. Several people saw him there, alone. He entered at about nine, and stayed until after midnight. There were credit card receipts to prove it. Since no one could disprove his alibi, he was released."

"So far you've just shown that my brother could not have killed his fiance. What makes you think differently?"

"This photograph of Richard on New Year Eve."

"What about it?"

"It isn't Richard. It's you. You were at that party weren't you? You called yourself Richard because he had let you borrow his credit card. You were twins. It can't have been the first time that you've impersonated each other. Just switch your jumper for a darker one. Like you said, people never really observe those around them."

Robert walked over to the arm chair and sat down. Sherlock brought the photograph and sat on the arm of the chair beside him. "Over time, I've learned to recognize your face. There's a dimple right here that becomes quite pronounced when you are uncomfortable. You don't like crowds, so you can see it here. Your brother doesn't have it. Also look at what's near your hand, a spy novel. Who would take a novel to a party? You would. Your habit of always carrying something with you when you go out."

"This is all circumstantial evidence: A book, a dimple? You think that will be enough to overturn a ruling?"

"Not alone, no, but where did you tell the police you were on new year's eve?"

"I was doing a complicated production reaction. The Sanger-Bosch process. It takes fifteen hours to produce a product and it can't be left unattended."

"You were seen going into the lab. You were seen in lab the next morning. But it was when I heard your alibi that I first knew you were lying, because you taught me the short-cut. You taught me your trick that allows you to finish the entire reaction in five hours."

"Have you told anyone else what you've found?"

"No. Mycroft called when he noticed that I had stolen his codes, but I got rid of him by telling him that you had found a job."

"Your deductive skills are very good Sherlock, but I find one very important flaw in them."

"What is that?"

"The evidence does not discount the possibility that I am the Black Neck killer. If so, you have just revealed yourself to a murderer. And we are very much alone here. No one would question it if I said that you had just gone missing this morning. So Sherlock, what do you think of that?"