Pa says if at first you don't succeed, try and try again. Our first plan was rushed because we didn't have time but now we've got a whole night and day, that's twenty-four hours and many, many seconds. We sit down at Table and I have to keep quiet while Pa goes into his Mind Palace. He says we won't have luck for a plan C so plan B has to be perfect.

I watch as Pa's fingers dance like his body. They twist in the air and he has his eyes tight shut. He is looking through his Important Shelves for information to build the plan. Pa says a plan takes a lot of thought, like when pirates attack other pirates to steal their treasure. I wait a while, but I get bored so I close my eyes and play with Redbeard. When I hear Pa breathe normal again, we open our eyes and look at each other at the same time.

"Have you built a plan for us to escape?"

Pa looks away. He's hiding something. "Yes, of course. Don't I always have the best plans?"

"Will I have to eat more eggs to get sick again?"

"No, absolutely not. They won't take you to a hospital, that's obvious, yet They are going to bring you medicine because They don't want you to die. So the answer is obvious." He stares right at me. "You're going to have to die."

I gasp. "But, Pa, that's stupid! If I die, I'll still be here."

He grins his big grin, the one he does when he's very happy. "Nope. Because you're going to play dead. Only Old Magnussen and the Witch will think you're dead."

"Will I have to hold my breath?"

"No, but you'll have to be not too floppy, not make any noise and be prepared to be a little claustrophobic. Think you can do that?"

"What do I have to do?"

"Come here, help me pull Rug out from under Table."

We shift Table and lay Rug out flat near Door. Pa lays me on the edge. I look up at him.

"What happens if this doesn't work, Pa? What happens if I make a mistake? Will Old Magnussen hurt you again if I-"

Pa cups my face in his hands and presses a big kiss on my forehead. "Everything will be fine, because we're going to practice this, okay? I won't let Them touch you. Do you understand that, Jack? I will dig myself out of my own grave to protect you. You're my world, Jack."

"Are there dogs in your World, Pa? Real dogs like Redbeard?"

Pa tickles me. "When you find uncle Mycroft, you can ask him for a dog. Now, I'm going to roll you up in Rug and you have to try and get out, all by yourself. Think of it as a game. Ready?"

"I'll try my best, Pa."

After ten goes I get tired and cross. Pa keeps yelling: 'Roll! Roll! Too floppy! Too stiff! Try harder! Keep quiet!' I want to cry but I don't. I want to prove to Pa that I'm a big boy. But I'm tired. I still feel sick and I can't breathe properly in Rug. Five goes later I finally unroll myself and I sit up angrily at Pa who's still giving orders and I shout "I HATE YOU!"

I didn't mean to say it. Pa looks sad and we hug. I don't say sorry, because I still want to cry, but I've already forgiven him, just like he's already forgiven me. We're family. It's what we do best with no words.

When we've calmed down, we try again. We find the best way to roll up Rug for me to get out. I know a lot of time has passed and I'm sleepy, but I must stay awake. Pa is counting on me.

"Truck. Wriggle out. Jump. Deduce. Somebody. You need to remember those five things, Jack. They will help you escape. The Witch mentioned the other night that Their gardener was leaving his pick-up here and They have the keys. They won't bury you on the Appledore grounds, because Their gardener will be suspicious. They can't put you in the back of Their car, because again, suspicions. So that leaves the pick-up which They will use to drive somewhere far away enough to avoid curious people. We're on the outskirts of London, which means They will pass housing estates and neighbours. So once you're in the truck, you will do the second thing: Wriggle out of Rug. Then you will jump when the truck slows down and get away quickly. As you go, you're going to have to deduce the people you see make sure they are clever and safe enough to save you. You've had a lot of practice with the people on TV so don't you worry. And that's when you do the final thing: Somebody. Pick a real person and stay with them. Tell them you need the police. You have to tell them everything, okay?

There's a pause where Jack worries his lip and cocks his head. "I don't know if I'll remember any of that. There's too much data."

"You'll be fine. I'll be talking to you in your head the whole time. Truck, Wriggle out, Jump, Deduce, Somebody. Do you think you can do that?"

"Yes, because you'll be in my head."

"That's right. Now, we need to prepare what you're going to say."

"To the police or the Somebody?"

"Both. You have to say that your father and you have been locked in a vault at Appledore. Go on, say it."

"Your father and you have been locked…"

"No, you have to say 'my father', not your father, okay? Try again."

"My father and you…"

"No, Jack, you're talking about yourself, remember? You say 'My father and I have been locked in a vault in Appledore.'"

"But you said…"

"Never mind. Tell the police about Room, okay? And Chain, you must mention Chain and Old Magnussen. But the most important thing is Appledore, do you understand? Because the police can't find me unless you tell them where to find Room. So you must tell them that Room is in Appledore. It's absolutely imperative, Jack."

"I've put it in my Mind Palace, Pa."

"Good boy. And tell them to find your uncle Mycroft Holmes. He'll protect you and take you to your grandparents. They'll all take care of you."

"What about you, Pa?"

Sherlock strokes his face. "I'll be alright."

"But when I jump and find the Somebody, where will Old Magnussen and the Witch go?"

Sherlock swallows. "I don't know."

"Yes, you do," Jack squints at him. "You're lying, Pa."

Sherlock looks unsurprised by this accusation. He sighs. "They'll come back here to see me. That's why you have to tell the police about Room in Appledore. So they can get here as quickly as they can."

"What happens if they don't make it in time? When will I see you again?"

Sherlock buries his face in Jack's neck. "You're going to have to be really brave."

"Will you live with me and uncle Mycroft?"

"I love you, Jack."

"Where will you be?"

"In your memories, Jack. I'll always be there for you in your Mind Palace."

"What about for real? Will we live in the house together?"

"I love you. I'm doing this for you."

"Answer me!"

Sherlock's breath is warm against Jack's cheek. Then he sits back and holds up Soft Ball between them. "Lift up your top. There's one more thing we have to do."

They lay together on top of Rug, Sherlock curled protectively around his son one final time. He knows that if Jack makes it, then he won't. But that's okay. Because he won't have failed Jack. The boy in question is staring up at Strip Light, unaware of his father's turmoil. His watch won't stop ticking, why is time going so fast, it has never gone so fast…

The door starts to beep.

Sherlock sits up. Jack gasps in fear.

"I love you. Don't forget that." He grabs the edge of Rug and rolls his son up, just like they practiced. But then Jack starts to wriggle and tries to fight his way out.

Sherlock panics. "Keep still!" he hisses desperately. Jack struggles for a few moments and then falls still. The door opens.

"Where's your son…"

They pause and stare at Sherlock who's shaking and crying on his knees. Their eyes drift to the rolled up Rug.

"It's all your fault," mutters Sherlock, raising his red rimmed eyes. "IT'S ALL YOUR FAULT!" he screams. "You wouldn't take him to a hospital and now he's dead!"

The Witch steps forward. "You let my son die?" she hisses.

Sherlock spits in her face. "He was never your son. He's mine, he's always been mine," he cries harder.

Old Magnussen steps forward and shoves him roughly aside. Sherlock watches with wide eyes as They unroll Rug. "Please," he whispers, "please don't make me look at the body. I don't want to remember him like that, you're not allowed to touch him…"

"Shut your mouth, if you know what's good for you. I swear that if you're lying…"

They all fall silent as Jack's arm flops out from under the last layer of Rug. Old Magnussen and the Witch seem surprised by this sudden turn of events. Old Magnussen searches for a pulse in Jack's wrist.

"No pulse," he states quietly and reaches to pull the rest of Rug off Jack's face.

"No," says the Witch. "I don't want to see his face, don't do that."

Sherlock makes a strangled noise at the back of his throat. He crawls over to Jack's body and rolls him back up, his hands shaking. The intruders watch on silently.

"Please take him away. I can't bear it, just take him and bury him somewhere safe, please," he sobs in despair. He cries, his limbs wrapped around the small form. Then gently this time, the Witch drags him away, while Old Magnussen picks up the rolled up Rug. He grunts as he lifts it.

"Be gentle!" wails Sherlock, reaching towards Them with both hands raised. "Be gentle!"

The Witch helps her partner carry Jack and Rug away. When They reach the door, Sherlock scrambles to his feet, tears still flowing down his face.

"Hey!" yells the Witch. "You know the rules! Face the wall while we tap the code in!" She struggles to lift her end of Rug higher.

At that moment, something rolls out at Old Magnussen's end and across the floor under Bed.

"FACE THE GOD DAMNED WALL!"

Sherlock is still struggling to breathe as he does as he is told. He listens to the usual six beeps and the door opens and closes. For the first time in five years, he's alone. Fear takes possession of every limb and he runs as close as he can to the door and presses his palms against it. He gasps for breath for several minutes until he can calm down. Then he walks back over to Bed and pulls out Soft Ball that had rolled out of Rug, the same one that he's used to fake a lack of pulse in Jack's arm.

He smiles. He's done his part. The rest is up to Jack.