Sherlock sits down next to Jack and rubs the palm of his hands together to keep them warm. He shivers in his thin T-shirt. "I've never told you my name, Jack. I'm called Sherlock. My surname is Holmes."

Jack bites his lip and thinks this over. "But you're Pa."

Sherlock smiles patiently. "Yes, but my name is Sherlock, just like your name is Jack. That's what my parents named me when I was born. My parents are your grandparents."

Jack looks confused. "You have more than one?"

Sherlock twiddles his thumbs nervously. "Yes, I have a father… and a mother. A mother is a lady. I grew inside her tummy before I was born."

"Do I have a mother? Did your parents live in Room too?"

Sherlock ignores the first question. "No, Jack, my parents never lived in Room. I wasn't born here. Old Magnussen and the Witch brought me here when I was sixteen years old."

"Where were you before?"

"I lived in a house with my parents and older brother."

"Like on TV?"

"No, Jack, for real, in a real house with a garden and I went to a real school with real people. The people on TV are real, Jack, they're being filmed, that's why we can see them, that's why everyone can see them."

"But it's not real, Pa."

"Yes it is, Jack, I promise you, everything is real. Where do you think Old Magnussen and the Witch go when They leave Room? They go back into their house. Room is a part of Their house, it's a part of Appledore."

"Does everyone live in a Room?"

"No, Jack, it's only us. We're not supposed to be here," he swallows and looks Jack in the eye, "We're prisoners, Jack. We're being controlled. It's Them that make the rules, but They're not allowed to. If I hadn't been kidnapped, neither of us would be here."

Jack pulls on his ponytail. "But we're supposed to be in Room because Room is real. You're not making sense, Pa."

Sherlock rubs his face in frustration. "No, Jack. The people we deduce on TV, they're real. Room is inside Appledore. Room isn't just a room, Jack. Room is a vault. We're being locked and kept in a vault. That's why only They can open the door."

"Are we locked in a vault for safety?"

"No. We're locked in a vault because They're cruel people and They enjoy hurting me. That's why I'm telling this. We have to prepare ourselves."

"Why aren't They allowed?"

"It's against the law. If the police knew we were here, they would rescue us. Your uncle Mycroft would rescue us. I've tried to escape numerous times, but there are two of Them and Old Magnussen, he's very careful and incredibly intelligent. That's how he was able to trick me in the first place."

"I have an uncle?" asks Jack, enthusiastically.

"Yes. You have a grandmother, a grandfather and an uncle. And if they met you, they would love you very much indeed," he sighs, "but that's not the point, Jack. Anyway-"

"Is my uncle real?"

"Jack!" snaps Sherlock, "forget Mycroft for a moment and just listen. I'm going to tell you a story, okay? Just listen," he takes a deep breath. "A long time ago, when I was little, I wanted to be a detective."

"You said you wanted to be a pirate," interrupts Jack.

"Well after that, I wanted to be a detective. But not an ordinary detective, no, I wanted to be a consulting detective, the first one in the world. The only one in the world. I was going to invent the job. But to start, I had to solve a case. My first one didn't go as well as planned. A boy drowned in a swimming pool, which is like a bath but bigger, but his shoes were missing. I talked with the police, but no one listened to me," his expression was faraway and wistful. "I never did get to solve it. I imagine it's still a cold case. But anyway, I didn't give up my dream. I started putting out ads, talking to people, trying to get someone to notice me, to let me solve their problems. And one day, a woman contacted me from America. She'd heard about me through her sister and she needed my help. She wanted me to prove that her husband was guilty of the crime he was on trial for. He was abusive and she wanted him to be executed, to get him out of her life." Again, his smile was wistful. "Mrs. Hudson was a lovely lady. It took me two months, but eventually I found the evidence necessary and long story short, Mr. Hudson received the death sentence. And I was in the newspaper and all other media for my exploits. I'd proven everyone wrong, especially my family. I could do it."

"What happened next?"

Sherlock's expression turns to stone. "That's when it all went wrong."

"Why?"

"For a while afterwards I felt as though I was being followed. At first I thought my brother had increased his surveillance on me."

"I like your dreams, Pa."

Sherlock blinks and does a double-take. "Sorry, what? What are you talking about, what dreams?"

"The dream you're telling me now. I wish my dreams were as good as yours."

Sherlock pinches the bridge of his nose between his thumb and forefinger. "This is real. Please let me finish. It's important," he grits out impatiently. "I thought I was being followed. But it wasn't my brother. It was Old Magnussen and the Witch. The Witch… wanted a 'friend' and she chose me. I looked physically appealing to Her and They were both interested in my intellect, so They contacted me. Sent me a letter telling me They wanted my help solving a case the police hadn't been able to handle, a violent murder. And I was so desperate to show off, to prove how clever I am that I rushed off to meet Them without thinking. I told my mother I was going to London to meet some clients. It wasn't far from where we lived. When I got there, They were waiting for me," he shakes his head, recalling his own stupidity. "He reached out to shake my hand, saying stuff about how They were my biggest fans. Then he stuck a needle in my arm and she shoved a bag over my head," he pauses, sadness etched across his face like paint, "and then I was here. Taken away from my life and my future to be locked in a vault against my will. So young and stupid. I never wanted to be here, Jack."

"I don't like this story."

"You have to believe me, this is the truth, this is reality, this is who I was before Room."

Jack pouts, "I want another story."

"Let's put it this way. What do people put in vaults? Secrets. And where do people hide their deepest, darkest vault full of secrets? In the recesses of their minds. That's where we are. We're in Old Magnussen's Mind Palace. That's what he calls this place, to taunt me. We need to prepare ourselves. We need to get out of here."

"Be quiet! You're lying!"

"Jack, please! PLEASE, Jack! I've taught you to deduce, to read people, to read me. So tell me, do I look like I'm lying?"

They glare at each other, breathing harshly, aware of the silence around them. "I don't like your story," whines Jack, "Tell me another one."

"THIS IS THE ONLY STORY YOU'RE GOING TO GET!" yells Sherlock, "NOW GROW UP AND LISTEN TO ME!"

"I DON'T WANT TO! I don't believe you!" They both stand, fists clenched as they try desperately to make the other see sense.

"Didn't you see what They did to me last night? They were going to hurt you, Jack! I'm trying to protect you! I'm trying to make you see that there's more to the world than this stinky Room!"

Jack starts to cry. "Room isn't stinky! Room is everything! I don't believe in you or your STINKY WORLD!" he shouts, throwing one last look of spite at his Pa, before storming over to Wardrobe and locking himself in.

Jack's shouts still ring in his ears, as Sherlock stares immobile at the spot where his son had been standing. A chill that has nothing to do with the temperature of Room seeps deep into his bones. A numbness floods him and he makes his way with difficulty over to Table. He sits on the edge, his feet dangling off the floor. The only noise is Chain jingling and clanking, a reminder of the truth that Sherlock has failed to make Sherlock understand. He listens for signs of life, but Jack is very quiet in Wardrobe.

His body starts to shake uncontrollably and he looks up at Strip Light. It flickers once. Warm tracks make their way down his face and it takes him a moment to realise he's crying. A high pitched keen escapes his throat and he clamps his hand over his mouth to keep quiet. He must not despair in front of Jack. No matter what, Jack must be able to depend on him. It's his own fault, he shouldn't have shouted. His body wracks with sobs he can't let out. Why can't Jack see? He mustn't blame him. Jack is only five and isn't prepared to have his whole world ripped apart by the person he trusts. He'll have to try another approach.

He's never cried so hard in his life. He breathes heavily into his hand, far too fast, the agony too strong for him to contain. He doesn't know how long it lasts, but he suddenly feels as though he's being watched. Hastily wiping his face on his T-shirt, he glances over his shoulder at Wardrobe. Jack wears an uncertain expression and he can't look his Pa in the eye. He shuffles around Table and rests his head on Sherlock's knee. The man's breathing is still stuttering and he struggles to get it under control. He tangles his fingers in Jack's hair and almost misses his son's whispered words.

"Tell me more about your World, Pa."

Sherlock scoops him up into a hug, a smile plastered onto his face. They make a deal: Sherlock will tell only the truth and Jack will believe him. He tells Jack of Mycroft, Redbeard and his life before Room and Chain.