So, the animators, for instance, rather than looking at this sort of classic mono fin swimmer where you have her knees bent and they are really obvious, we tried to work out how could we break up the joints, so it’s more like a fish tail.  Instead of the knee joint, although we still want a hint of that, we might have multiple joints.  We looked at the whole anatomy of how this would work.  One of the images that inspired Rob Marshall was an image which had a glamour model on a beach, in a towel that is almost like a sheer fabric.  He really liked the fact that you got a hint of her legs through the fabric of this towel, so that was a quality he wanted us to think about.  We actually took that and said, “You know what, why don’t we make it like the mermaid has a scaly inside, but then has this sort of almost jelly fish or slightly translucent, transparent membrane.”  That might be useful because it might help us with the transformations.  So coming up with that was definitely a challenge, but a really fun part of it.  But then once we came up with that, it was, how do we execute this sort of thing?

There was a lot of stuff that we had to deal with.  There were a lot of mermaids and they were fighting, so we had crowd scenes to deal with, we had to work out where to package up the animation, because the mermaid design had a lot of trailing, beautiful flowing tendrils, and kelpie like growths, that came out of their hair.  We did a lot of work to come up with ways to simulate that in a way that we could then transplant between different models and across a pack of fifty mermaids.

Ironically of course, one of the biggest curve balls that hit us during the production was that quite late on, the design changed.  It was really important to him [Rob Marshall] that out here in the mermaid’s arena, she was a beautiful woman. But the argument had always been that the other mermaids that were attacking the sailors, earlier in the film, could be a little bit more aggressive and creature-like and be a little bit more different, not so human.  But as the film jelled, the director decided, “You know what, I really want them all to be human. Particularly when they are out of the water they should pretty much just look like the actresses that we photographed. ” 

Captured ships, frozen in time. Image © Disney Enterprises Inc.

Now of course, because these creatures attacking the pirates weren’t going to be actress-like, we hadn’t filmed actresses attacking the pirates.  All of the films where we tried to make digital humans, it was a pretty big challenge, and particularly a big challenge to be faced with only a couple of months left in the production.  So, we collaborated with the director, tried to work out how we would do this, and with the studio-side effects supervisor Charlie Gibson, we decided to shoot some actual footage of people that we could use.  We had material for a couple of the key performances and then we had to step back and say, “How do we make these creatures look more real?”  Instead of them having long kelpie tendrils of seaweed, they will have to have hair, which is a whole different can of worms.  It’s not [like] simulating long cloth-like objects, you are now simulating individual hairs, and it’s a big complication.  So we said we won’t be able to do that, we are going to have to color them so that they look like [they have] hair.  One of the things that really worked in our favor was he [Rob Marshall] really wanted to play [the mermaids] quite mysterious and dark.  You don’t really see what’s going on and he felt it would be a lot scarier that way.

It actually did work.  We went with the more human look, since we had used real people, and we had already done a fairly thorough job of working out how to integrate the mermaids with the live actors, add scales to live actors, because we are doing that with the main mermaid.