It strikes me that the movie siren costumes are really very thin in the fingertips - you can practically see the outline of their nails through it. I suspect they may have nothing but a single layer of latex over their fingers - in fact, I wonder if the whole suit might have been done like that, and layered over some, er, extremely serious underwear. Looking at it again, though, my guess would be that most of it is coated spandex with some plain latex in areas that need a lot of give or are critical to dexterity, like the fingers. Finding stretch fabrics that don't just look like spandex is difficult; I've tried latex coating it myself and the best I could do was a sort of sponge-stippled texture that was OK but not applicable to every situation. You can buy sheet latex but then it just starts looking like fetish gear which often isn't quite the idea... Underworld got away with it because she was a vampire!
Also I think that the general trend of girls in catsuits is particularly daring in and of itself, and I can only applaud the courage of people who are willing to don this stuff. In an original design recently we steered away from it, even though the design direction was vfert Apppleseed movie, Ghost in the Shell style in which a lot of women wear skintight bodysuits under hard armour. We nixed it simply because if you're going to do it you have to do it exactly right or it instantly looks terribly cheap and exploitative. Having seen done of the work here I'm beginning to reevaluate that decision to some extent, but I'd be interested to know what it costs to get these patterns drawn up, if that isn't an impolite question.
As I understand it there is a whole sub-discipline of tailoring dedicated to this kind of stuff (usually it finds use in swimwear and sports clothing) and it is considered quite specialist even by experienced costume people. It's pretty impressive to see it being done so successfully here! Are you folks sure you don't do this for a living?
Even at the very highest end, though, it seems to be a field involving a fair bit of compromise. Part of the trick is precision - is it me, or do the other sirens' suits fit fractionally less well than Gem's - but since fabric will not stretch infinitely there are always points where it works less well, often around the shoulders where there's a lot of motion to deal with. There's a scene in the movie where the Gem character sits with her arms speed across the back of a seat and the suit webs out quhite visibly under her arms, which is presumably a side-effect of not having a lot of excess fabric there when she's in a more everyday pose.
Please excuse such a stream of consciousness; I'm just thinking out loud really. Does any of what I've said make sense to anyone?