Once again, Sherlock was visiting his incapacitated brother. Or rather, the hollow shell that was left behind by the man who once ruled Great Britain with his Great Black Brolly in hand.

Sherlock didn't speak. There was something horrifying about having his words bounce off ears that should be working, and falling instead into a black void. So he sat, and observed. Nothing. No change, no indication of life. Mycroft, brother mine, what has she done to you?

Sherlock stood up suddenly. There was only one way to find out.

She sat cross-legged on the floor, and waited. She hadn't expected to wait this long. Yet she knew he would come. Soon, Sherlock would come and play with her, and it would be just like the good old days. She would make him him laugh, and cry, and scream, maybe even all together at once.

Sherlock was her favorite. Like her violin, he was so easy to play, and made such beautiful sounds. Beneath her skillful fingers, he would vibrate with excitement, or tremble with fear. He was never dull, despite being stupid. She couldn't wait to play.

She frowned suddenly. It was a pity she had saved the doctor from the well. Now Sherlock would be busy with him, and would forget all about her. But she had been confused, and Sherlock had convinced her that he could help her land, but she needed to save his friend first.

Eurus didn't understand it, not really. Why did Sherlock form such strong attachments to ordinary humans? The redheaded little human was gone for a long time, yet Sherlock still seemed upset about that. Now it was the little blond-haired man he was attached to. Humans, so tricky. Letting themselves be ruled by convoluted emotions, to their own detriment. Fortunately, she was above all that.

She strummed at her instrument as she waited. I that am lost, oh, who will find me...

Sherlock would find her. She wanted to play.

"Anthea, I need a favor," Sherlock spoke into his mobile.

"No, it's not about Mycroft. I need to see my sister. Yes, that one. How many other hidden sisters do I have? I'm not forgetting what she did to Mycroft. In fact, that's exactly why I need to go see her. Eurus is the key to Mycroft's recovery.

"What do you mean, she doesn't speak? Get me in. I want to see for myself. Anthea, please. Do what you can. I'm afraid this is our only hope."

"Eurus," Sherlock greeted his sister softly. "How are you doing?"

Sherlock saw the spark of recognition in his sister's eyes. He continued talking, in the same voice. "I hope you're feeling well. Is there anything I can do to help you?"

She was looking straight at him, without blinking, but didn't respond. Sherlock resumed his monologue. "Would you like to hear a composition I came up with? Perhaps you can play along, after I play it once."

Through his sister's silence and unwavering stare, Sherlock played. When he finished the piece, he looked at her expectantly. She stared some more.

Sherlock was beginning to feel slightly unnerved. He put his violin down, and returned her intense gaze. For several long moments, brother and sister looked at each other silently.

"Alright, Eurus, I know you're there," Sherlock said finally. Far from being catatonic, as the guards described her, she was hyper-alert and aware of her surroundings. She simply chose not to interact. Sherlock felt confused and uneasy, unsure of his next step.

"Do you want me to come back and play again?" he asked gently.

Eurus blinked.

"Ah, I suppose you do." It appeared she was playing a new game. Where as before she had reached out, reached through the iron bars of her imprisonment, and practically shook them by the shoulders to get them to listen to her, now she had changed course. She wanted Sherlock to reach out, to reach into her mental prison bars and and make contact with her.

Poor Eurus, Sherlock thought. She's just a lonely little girl, crying out for help, and no one can hear her. Locked away in her own mind, just like a prisoner, just like- Mycroft...

Sherlock jolted back to reality. He was here with on a mission. On two, actually. One was reaching out to Eurus, and the other one was helping Mycroft. He thought he could accomplish both together, just as he had done when saving John.

He smiled at the bittersweet memory. By reassuring Eurus that he would be there for her, he had gotten her to save John. Perhaps he could try that same technique now.

"Eurus," he addressed her. "I'm here now. I want to be here for you. I can be your controller on the ground, helping you land. But just like a pilot, you need to interact with me, so we can land your plane together."

Slowly, she blinked.

"Please tell me, sister mine, what have you done with Mycroft?"

Eurus smiled.

Her smile was anything but reassuring. In fact, it sent shivers down Sherlock's spine.

"Eurus, you have to answer me. There's no way I can come and play with you if I'm distracted by the mystery of what happened to Mycroft!"

A fire was now burning in his little sister's eyes. She picked up her violin and began to play, skillfully and soulfully.

I that am lost, oh, who will find me...

"I don't understand, Eurus. I solved that puzzle already! Do you remember? I found you in your room!" Sherlock was more than confused; he was actually scared. There was something going on in here that he didn't understand.

Eurus began playing again, but there was something wrong with her playing. She played the same few notes over and over again. Sherlock concentrated. She had played the first three stanzas regularly, and now was playing the fourth. Specifically, the second and third lines of the fourth stanza.

Who now will find him?

Why, nobody will

Nobody. Nobody will find him. Of course.

"Eurus, you better tell me what you did to Mycroft, or you will find yourself all alone again!" Sherlock said sharply, his voice tinged with panic.

Eurus picked up her bow, and began a new tune. Sherlock's jaw dropped open. Was she playing country?

The detective didn't like to admit it, but he knew some country tunes, too. Only by sheer coincidence, of course, and not because he would ever condescending to playing folksy tunes instead of classical. This particular tune was even played by the Royal Philharmonic, so it couldn't have been that bad.

So Sherlock could admit that he recognized the tune: "Try a Little Kindness" by Glen Campbell. The message was startlingly easy to decide. Eurus believed she had done Mycroft a kindness. It was eerily reminiscent of Mycroft's words, when he had explained why Eurus's survival had been kept from their parents: it was a kindness.

"Why is it a kindness? What does Mycroft gain by being rendered into a shell?" Sherlock asked accusingly.

Eurus didn't respond. There were no more clues to be had. Sherlock would need to figure this out by himself.

"Goodbye, sister," he whispered, distraught. "I'm sorry, but I don't think I will be coming back. The games you are playing are too dangerous. Instead of saving you, I think I am getting lost myself."

On his way out, Sherlock heard Eurus play again. She was now playing Wagner's famous lullaby.