The cell is austere. Bed, table, chair, shelf, barred window. Basin, behind a door the toilet. More or less. A look out of the window confirms my supposition, Her Majesty's Prison Full Sutton, York.

Of course, I am a category A prisoner. "Those whose escape would be highly dangerous to the public or national security," my mind delivers via my inner Mycroft. "Offences that may result in consideration for Category A or Restricted Status include: Attempted murder, Manslaughter, Wounding with intent, Rape, Indecent assault, Robbery or conspiracy to rob (with firearms), Firearms offences, Importing or supplying Class A controlled drugs, Possessing or supplying explosives, Offences connected with terrorism and Offences under the Official Secrets Act."

I can tell that something is wrong with me when my mind quotes Wikipedia.

So I am located amongst the most dangerous prisoners of the UK. How fitting. Not that I am likely to meet any of them. After my (short, but disastrous) time at Belmarsh Prison in 1998, it was understood between Mycroft and me that contact with other prisoners should be avoided at all costs.

The memory of everything that happened after I … after the shooting (can't even bring myself to name what I did. Tedious!) is still blurred. I need to access my mind palace to recall it all more clearly.

There is a room for re-watching the parts of my life my conscience missed the first time. It used to look like Auntie Rose's living room. Now it is the (only) cinema John forced me to visit to watch a Bond film with him four years ago.

I can tell that something is wrong with me when my mind palace is black and white.

Even here my memory is fragmentary. Apparently I was pushed to the ground by one of the marksmen, firmly fixed. Facing Magnussen's body. His empty eyes staring at me. His glasses askew on his nose, arranged like it could be seen in an overly dramatic B-movie. I want to get a (last?) look at John, but my head is fixed, too.

I was pushed into the helicopter. Of the ride I have no memory except the look on Mycroft's face. (Disappointed? Sad. Scared?)

I was pushed into a grey room where an unimpressed security guard undressed me, searching for guns in my clothes and for drugs in the most private places. Try to delete that memory instantly, but it does not work.

In my cell, rules were read to me. (No contact with other prisoners. One visitor every two days. Daily solitary shower under supervision. Access to the library for good conduct. Thirty minutes solitary workout under supervision.)

I must have slept, eaten, gone to the toilet, but the memory of that is inaccessible. A memory that floats to the surface again and again is Magnussen's dead face.

I think there should be feelings attached to those memories, but there are none. "Bit not good, that" my inner John says with pity. He is translucent, barely visible. He offers me some of his virtual popcorn. I decline.

There have been times when I was isolated before, during what John calls my "hiatus" and before. It never bothered me, for my mind palace has always been a perfect hiding place. Now its colourlessness unnerves me. Every wall, every door is plastered with a poster of Magnussen's dead face. Every person I conjure is translucent.

I get out of there before my mind snaps, but only scarcely so.

When lunch is brought to my cell, I (politely) ask for access to the library. It is denied. I need to show good conduct first. I start to do so by not arguing. John would be proud.

Or would he?

I am still not good with emotions, but I am fairly sure that he is angry with me. (In the long run, he surely will be grateful. When he will hold his baby in his arms, for example. But now, he must be terribly angry, because I managed, once again, to do the only thing he asked me not to do. I left him. Again.)

I spend some time calculating the number of bricks in the walls. Then I delete the result so I can calculate it again tomorrow.

I spend some time looking out of the window, extrapolating tomorrow's weather. (Sunny at first, cloudy in the afternoon. Still too warm for December.)

I am ushered to a small workout room that smells like sweat. A guard (not happy about working on Christmas) watches while I obediently continue the programme I have learned in rehab after I got shot. My inner clock is precise, I am finished after exactly thirty minutes.

I am ushered to the showers. The same guard watches as I undress. I try to deduce if he enjoys his job more, now that I am naked, but fail. Most likely he is simply bored. I am torn between wanting to stretch my stay under the shower to maximise the time I am to spend outside my cell, and hurrying to get away from my guard's impassive observation and get dressed again. I cannot make up my mind, so I simply wait until he tells me to finish.

I can tell that something is wrong with me when I am not only relieved but happy to see Mycroft that afternoon. The first thing I feel all day. He is oozing with concern. "How are you?" he asks. I don't know.

"John has asked permission to visit you," he tells me while watching me carefully. Only one visitor every second day, I recall. "I could arrange for him to come here tomorrow," Mycroft goes on, still scanning my expression carefully. And expose me to John's anger and (How does he feel about having watched me turning from a dragon slayer into a murderer? How does he feel about me leaving him again as a direct result of that?) disappointment? Rather not, thank you.

Mycroft stays for another hour. Tells me he is already negotiating to turn my imprisonment into some kind of service to the crown, but so far Serbia is the only alternative. I wonder if I really deserve something else.

Only when he is gone again do I realise that I have not spoken a single word since asking for permission to visit the library. "Bit not good, that" my inner John says again. I can only agree with him. Silently.

The second day is nearly identical. I have breakfast. Calculate the bricks in the wall and delete the result. Have lunch. Forecast the weather. Do my workout. Take a shower. Surprisingly, Mycroft shows up again. He brings along a Stratego game. We play eight matches. I lose every single time. He leaves. I have dinner. Go to bed. Lie awake until a restless sleep overpowers me. I don't speak a single word, not even in my nightmare.

The third day is nearly identical. I have breakfast. Calculate the bricks in the wall and delete the result. Have lunch. Forecast the weather. Do my workout. Take a shower. Mycroft shows up again. He brings along Stratego again. We play six matches. I lose every single time, but it is a lot closer now. He leaves. I have dinner. Go to bed. Lie awake until a restless sleep overpowers me. I don't speak a single word.

The fourth day is nearly identical. I have breakfast. Calculate the bricks in the wall and delete the result. Have lunch. Forecast the weather. Do my workout. Take a shower. Mycroft shows up again. He brings along Stratego again. We play four matches. I win the last. He leaves. I have dinner. Go to bed. Lie awake until a restless sleep overpowers me. I don't speak.

The fifth day is nearly identical. I have breakfast. Calculate the bricks in the wall and delete the result. Have lunch. Forecast the weather. Do my workout. Take a shower. Mycroft shows up again. He brings along a Reversi gameboard. We play ten matches. I lose every single time. He leaves. I have dinner. Go to bed. Lie awake until a restless sleep overpowers me. I don't speak a single word, not even in my nightmare.

The sixth day is nearly identical. I have breakfast. Calculate the bricks in the wall and delete the result. Have lunch. Forecast the weather. Do my workout. Take a shower. Mycroft shows up again.

And with him John.

I turn away from them so quickly that our eyes only meet for less than a second. Memories of Mary surface all of sudden. Sitting in our living room. Telling John she does not want to watch how he stops loving her. I finally understand what she means.

I can hear a pair of footsteps moving away (Mycroft), another pair coming closer (John). Coming to a stop right behind me. "Sherlock, ..." he starts and stops again. Impossible to deduce how angry he is with me. Or if he still loves me. (Why should he?) I wish I would still not feel anything.

I silently wait for him to tell me whatever it is that made him take the long journey from London to York. (By helicopter, provided by Mycroft.) Hear him clearing his throat. Brace myself (as much as possible). My body tense, my mind too. Come on, hurry up. Tell me you are angry with me. Tell me that this has been the last time I left you because you are leaving me now. Tell me how you will raise the baby with or without Mary, but definitely without me. How you will grow old without me.

"Sherlock, I am sorry you had to do that for me," he says then, his voice genuinely sorry. His hand softly stroking my back. "I should have been the one to shoot Magnussen, not you. I can never make up for that, love."

That is John for you. Most people (including me, apparently) get him wrong. He is not the Damsel In Distress. He is not the White Knight. In reality, he is the Pauper that turns out to be the real Prince in the end.

"You don't have to," I say softly, my voice harsh from not being used for nearly a week. I find the courage to turn around, look into his (still loving, sad) eyes. This breaks the last straw. I stumble into his (always open) arms, hide my face in his (soft) jumper. Feel him embracing me, steadily, then gently rocking me as I cry over the innocence I've lost the second the bullet hit Magnussen's brain, over the future John and I most likely will not have, over the baby I will not see grow up.

When I am finally done crying (after one hour and thirty-eight minutes), he continues to hold me while I tell him about how it felt to kill (terrible, heart-wrenching, destructive), how I am scared to lose my mind in solitary confinement, how my mind palace betrays me, how much I love him, how I am scared for him and the baby now that he has to face Mary without me, how I do not know what will happen to me and how I missed him. The only thing I do not tell him is that Serbia is really a death sentence, not an escape.

Then he tells me how he still believes that Mycroft will come up with some clever trick, how he will not believe that I will end up in prison for good, how he loves me and how everything will be all right in the end.

I still don't know what will happen to me, or when it will happen. All I know, all I need to know right now is that John's arms will always be open and that killing Magnussen was a small price to pay to protect the love of my life.

Notes: The quote on category A prisoners is taken from here: wiki/Prisoner_security_categories_in_the_United_Kingdom