It's all a bit strange, indeed, and I don't have any answers to your questions.
About Sherlock knowing or not knowing that Mycroft has imprisoned Moriarty and the Holmes brothers having planned this together: to me it would only make sense if they had planned this within hours after the incident at Dewer's Hollow, some time between that evening and the next morning. We know that they are very clever, so I guess it is imaginable that it would only take them a couple of hours to plan something like this.
Still, something doesn't feel right about this explanation to me. And it might get even more weird in the Special or S4, should Moriarty indeed still be alive. 

Yeah, well, we see them talking on the phone in THoB twice, of course they talk about something completely different, but it might help to make us believe that they are talking on the phone on a more or less regular basis (during that episode). But I agree, that part of the explanation in TEH comes pretty much out of the blue. It sort of makes sense, but there is a lot of stuff in it that we just have to believe without any visible evidence. 

Good question about Lestrade. I'm sure he didn't know that Sherlock and John were there, so why indeed did Mycroft send him there? Maybe to make sure that Sherlock stayed there long enough for Mycroft to arrange a deal with Moriarty? I don't know, it's all a bit... weird. 

...and now you edited your post, Susi, and part of my answer doesn't make any sense anymore. 

Last edited by SolarSystem (October 27, 2014 9:36 am)

(Just saying that I feel unable to participate here without waving with "M-Theory" all the time, and that is another topic and I'm not yet ready to do that, so, sorry, girls!  )

I'm also waiting, Harriet. 

Susi, maybe Sherlock and Mycroft both wanted to somehow outsmart Moriarty. Holding him in a cell until the end of his days might not have felt like a real victory. Personally, I don't like the idea that the Holmes boys might be too proud to just keep Moriarty in a cell and be done with him. Do they both really need to play the game? Do they need to 'win' on their own terms?

Let's face it, from all we know at this point it was unnecessary to let Moriarty walk free and then put him on trial to let him walk free again. Why not leave him rotting in prison in the first place? Because that's not very appealing for a tv audience, right. But of course they could have played the whole thing completely different from the start - or at least after ASiB. There was no real reason to have him in prison at the end of Hounds, was there? Maybe apart from the dramatic effect. 

Let´s not forget that Moriarty is not merely one person - it is also a criminal organisation involving many members. Organisation strong enough, so that it can cause mayhem through breaking into Pentonville Prison, Bank of England and the Tower in a few minutes and yet remain completely unharmed, with it´s active members undetected.

Holding up Moriarty in a cell, with a knowledge that his minions would continue his dirty work and will be able to get him out of the cell in time through some collaborators, would be completely pointless. So letting Moriarty go and to prepare some plan of how to eliminate him and shutdown his organisation as well would be a wiser solution.

We don´t see this in THoB yet, because the resolution to end Moriarty´s organisation through some devilish plan had to take place close afterwards. In TRF we see the situation through John´s eyes - and since John was deliberately left out of this, he doesn´t notice the slight signs that such a drama is taking place behind his back. What´s more, Holmes Brothers outwardly pretend that a dispute is going on between them in TRF, so as to mask their secret dealings about Moriarty and his gang from the public and from their friends as well.

As to why Mycroft allows his brother to be endangered by the dangerous game between him and Moriarty in TRF - both brothers know that of all existing things Sherlock has a strongest appeal to Moriarty, so Sherlock probably volunteered to act as a bait (which also conforms to his own, reckless personality). Also, their plan of eliminating Moriarty´s organisation was obviously not firmly delineated and it had to undergo many changes according to Moriarty´s unpredictable moves. Hence, they had multiply plans for everything - like 13 ways for Sherlock of how to escape from the roof at St. Bart´s.

I just want to state once again for the record that I will be seriously dissapointed if Moriarty is really still alive.

The creators have said more than once that there is an arc to the show as a whole and I am quite sure that something important will happen to Mycroft/be revealed about him in the special and/or series 3.

Because one has to look at the development of his character as a whole and in series 3 there is a big blind spot regarding Mycroft - his attitude towards Mary and Magnussen; John, Janine, Mary, Lestrade all visiting Sherlock in hospital while we never see his reaction to Sherlock being shot; his possible role in the (faked) return of Moriarty; the mysterious "other one" who by no means has to be a family member … On the other hand his love for Sherlock is shown more blatantly than before. This is going to be very interesting. 
 

I agree (apart from the roof scene but that is for another thread). I always felt that his confrontation with Richard Brook was genuine. The scene still makes my hair stand on end. His shock seems very real and his abrupt reaction in the street followed by the scene in the lab do confirm this IMO. 

Oh, I believe the "Richard Brook" appearance in Kitty´s flat was a real shock for Sherlock even if Sherlock and Mycroft already had a "Moriarty elimination plan". As I mentioned above, Moriarty´s moves were very unpredictable and the Holmes Brothers had to adjust their plan to them quite quickly. This Richard Brook confrontation was one of such crazy, strange moves that Sherlock had no chance to predict, hence the aura of strangeness and shock we could feel in the scene.

Still, when he ran away from Baker Street 221B with John in front of police´s noses, it was a deliberate staging of a desperate escape from Sherlock. He mentioned it even when he told John: "I am doing exactly what Moriarty wants. I´m running away." If you think about it, Sherlock could disappear much sooner - he was forewarned by Lestrade that they are coming for him and he had no logical reason to wait, let himself be arrested and escape only after all that. The only reason for his illogical waiting is that he wanted to make a grand scene when escaping, thus persuading Moriarty that he is really desperate and at his wits end.