After two viewings, some semi-coherent thoughts are bubbling to the surface of the old brain box. It's still way too early for anything really analytical, but first impression are that this episode isn't going to support much analysis anyway.
1. It won't be a surprise to anyone here that I LOVE the MI6 scene (Both chortling and squeeing took place. D notices FTW!!! Someone did his homework. *pets the superspyness*).
2. Code names: assuming that the secretary doesn't have a spy name, then that means we learned Sherlock and Mycroft's spy handles in this scene. Seriously, I thought I was going to have some sort of brainjoy meltdown. Love (confirmed as Lady Smallwood), Antarctica (seriously, does anyone think this might refer to anyone other than Mycroft?), Langdale and Porlock. The latter two are obviously based on names of characters in The Adventure of the Three Gables and The Valley of Fear. Porlock is the interesting one: it's the surname of a confederate of Moriarty's, who later turns against him. So either this is a fantastic red herring, or someone in that room (Sir Edwin, presumably) might very well have been in league with Moriarty in some way. Or maybe that's just my head canon/fic leading me astray. I'm very much looking forward to finding out which, though I don't imagine they'll give it to us.
3. The story of the merchant of Samarra turns up three times in the episode; I wonder why? It doesn't connect particularly well, even in the conclusion with Mrs Norbury. It seems a bit tacked-on, so I wonder if it's foreshadowing for the following episodes (must give this some more thought).
4. Lots of annoying scene transitions. After the moderately interesting one after the first scene at the shark tank, they kept cropping up like a rash. I'm assuming it was Moffat that insisted they go in. Fuck they're boring.
5. Mycroft and Mary and AGRA: well, I'm glad to see that the idea that Mary had ever been working for Mycroft is dead (though, can we assume Mycroft's telling the truth?). I hope this notion is gone for good; I always thought it was trite. But we still don't know how Mary ended up in John's life. It's simply too much of a coincidence that they ended up meeting while Sherlock was away. (Please please, please let her have been working for Magnussen!)
6. When John flirts with the woman who follows him off the bus (and did she not notice the wedding ring? if she did and approached him anyway, well hello, skanky!), he never tells her the daisy was for his daughter, that he has a daughter, or that he has a wife. Is this how "three continents Watson" is being inserted into this storyverse? If so, ugh. Adulterous-asshole-John I'm really not interested in, though I concede it is in character for John to lash out in a really stupid way in retaliation for Mary and Sherlock "abandoning" him.
7. I love, love all the Magnussen/shark references. They shot two scenes in that bloody tunnel, and I hope this means we see more about/references to my fave villain.
8. John is a doctor, and he just sat there moping while his wife was dying. Really? While I've never been the biggest fan of Mary, killing her off in this particular manner was horribly trite. The most interesting aspect of Mary's character was that she wasn't heroic; now she's been effectively neutered as a character, just another woman sacrificing herself for Sherlock. Fuck that, I say.
9. The scene with Sherlock and Ella makes absolutely no sense, other than maybe Sherlock going to her to trick/deduce information out of her about John. Because there's no way Sherlock would go to a shrink, especially one whose skills he's already dismissed.
10. I love Mycroft's empty fridge. Though the takeaway menus blow away at least three elements of head canon about him, and to be honest diminishes him a bit in my eyes. Oh well, he's allowed to be ordinarily about this, I suppose. (*grumbles*).
11. NO MORIARTY!!!!! Not even a mind palace shot, nothing. Halleh-fucking-lujah. And a Gatiss script, at that. Do we dare hope that the "fascination" is over and done with? I'm sure he'll be back in TFP, but with another middle-episode baddie coming up, I think we can assume we might actually get through two of the three episodes without a view of Voldiarty.
12. The call to "Sherrinford". I thought it was interesting that he used his land line to call. Whoever "Sherrinford is, it's someone whose number Mycroft doesn't have on his blackberry - why? To me, there's whole lot of probably overlapping possibilities here:
a) it's someone Mycroft doesn't call often, and/or;
b) it's someone who's solely a personal connection (such as family), not a professional one (or the number would be on Mycroft's work phone as well as his home one), and/or;
c) it's someone Mycroft doesn't want anyone to know he's in contact with (mobiles can be hacked, but unless your land line is a VOIP phone, it can't be, so keeping the number off his mobile ensures it's almost impossible for anyone to know he's called this person).
That's it for round one! I'll probably have more thoughts after watch number 3.
On a more general note, I'd give this one a solid 7.5/10. Not a hit out of the park, but a solid transition episode, with a weirdly-executed, tacked-on death at the end.
I'm very much looking forward to the next one; Toby Jones is an amazing actor and I've never seen him play a stone-cold villain before. He will be completely awesome and I'm really looking forward to it!