The veil. A politically loaded symbol. It carries all sorts of old semiotic baggage, of course. Weddings. Widowhood. Ladies in Conan Doyle who want to hide their identities (thus it has a trajectory into the figure of Madame Vastra via Victoriana). In genre TV these days, a woman wearing a veil is likely to be a tragic or vengeful figure, hiding a facial scar of some kind. (See 'Silence in the Library' / 'Forest of the Dead'.)
The veil is thus something that implies a particular set of social situations for women. The connection appears to be the concept of separation. The veil is a boundary between the woman and society. It creates a space in which she can hide her unsightliness, either disfiguring grief or grievous disfigurement, from those who don't want to have to see it. The wedding veil is lifted as the woman is taken possession of in the marriage ceremony; thus it is there to emphasize her acceptability by temporarily putting it in doubt. It is, of course, the symbolic tearing of the hymen. The man takes possession and breaks through the barrier. All very nasty. Not to mention anatomically inaccurate.
Vastra's veil takes on enormous significance in 'Deep Breath'. Indeed, the whole episode is full of talk about faces, with them being stolen, exchanged, worn, hidden, changed... with them contemplated in mirrors.
Vastra is married to Jenny (by Silurian law perhaps?), and yet this marriage hardly seems to have anything to do with Vastra's veil (unsurprising, given that it is black rather than white), since Vastra and Jenny's relationship fails to fit easily into any patriarchal schema. There is no sense in which Jenny owns Vastra. Indeed, the power relationship appears to go the other way (with implied consent).
There is a sense in which Vastra could be said to be mourning. She is an isolated figure in some ways, cut off from her lost people. But this is hardly emphasised at all. She doesn't seem tragic, and her complete lack of vengefulness is so complete as to be worrying (to me anyway).
As mentioned, she reiterates - in some ways - the figure of the veiled lady from Victorian popular fiction, via her place in the regurgitated Victoria trope pyramid. But she inverts this, to some degree, by being the detective. Her veil isn't to hide her secrets from the investigator, rather it is to hide the secrets of the investigator from the client - as long as is necessary.
There is another significance to the veil in our culture at
this time: the immensely freighted issue of the hijab... or perhaps I
should say, the immensely freighted issue of Western ideas about the
hijab. I've likened the Silurians to the Palestinians before now, which
would obviously chime... especially when you remember that Vastra has plonked herself down at the hub of the British Empire as a kind of refugee, and the British Empire was mucking around with the area that became Palestine from the 1830s onwards (though Victoriana places Vastra well before the disastrous British interventions of the early 20th century).
choice to wear the veil makes her a better representation of this issue
than we tend to get from the culture industries. It's a widespread prejudice in Western culture (which imagines itself to be post-sexist) that all or most Muslim women wear the hijab and other such articles of clothing because they're forced to by Muslim men. If Vastra's veil can be tied into our wider 'debate' about this (with 'debate' here meaning the sickening display of Islamophobia dressed up as liberal concern for women's rights) then it looks quite good.
We're onto something with the issue of disfigurement too. The figure of the disfigured woman hiding herself (and thus also her identity and vengeful agenda) is overused and overfamiliar, and laced with some quite nasty assumptions... but Vastra isn't disfigured. Rather, as she herself says, it is Victorian society that considers her disfigured. This is a more-or-less direct connection between race and social exclusion (with race filtered through the SF concept of the alien), and also connects with a critique of attitudes towards women who don't fit the sexist concept of acceptable female appearance. (Slightly undermined by Vastra's fixation on Jenny's prettiness.)
At first sight, this reading also seems undermined somewhat by the way in which Vastra can walk around on the banks of the Thames, surrounded by people, without wearing her veil, attracting no attention. On the other hand, maybe those people do see the veil even if we, the viewers, don't. Because - and this is the really interesting thing - Steven Moffat now seems to be implying that the veil is only visible to people who feel some need to see it because they are unprepared to look the facts about Vastra in the face, as it were... and, by implication, to see past their own prejudices. This, I suppose, is how to read Vastra's comment that she wears the veil as a judgement on others.
Read this way, the veil is a way for the viewer to judge themselves. That's actually quite good, and more pleasant than my initial thought, which was that the "judgement" comment was a rather weasily way of making the need to escape the consequences of social marginalisation into an empowered choice made by the victim.
If the veil is a property of the viewer's perception, that would fit into Moffat's established habit of treating the camera as a diegetic eye (see Phil Sandifer on the Weeping Angels and the Silence for some interesting thoughts on this). It is also, I suppose, the reason why Clara suddenly starts seeing Vastra's veil when she is having problems accepting the new Doctor, and confronting Vastra's support of him. By that logic, it is also why the veil vanishes when she gets her talking to from Vastra. The thing that makes this work is the way Clara's acceptance of the Doctor and Vastra comes via her giving Vastra a severe and confrontational talking-to, which concedes Vastra's basic point while also objecting to her arrogant way of making it.