Tansley was drawn to the idea of making a documentary as soon as she heard about the project.
"It was like a lightbulb moment and I thought, 'that would be a fascinating process to follow' for a number of reasons," she says. "There's obviously the inspiration for the ballet, which is The Piano the movie — and that's very well-known and iconic in New Zealand — then there are all sorts of other threads in that you have a European choreographer coming here, working with an NZ company with a story, or drawing from a story, which is very resonant."
Tansley and the crew travelled to Europe to record the Bubeniceks in their home environment and are now spending many hours at the RNZB's Wellington headquarters filming rehearsals and interviews with those involved in every step of the production. Dance footage is being filmed on two cameras so once edited it will be more encompassing.
Her first feature documentary film, Crossing Rachmaninoff, premiered at the New Zealand International Film Festival in 2015 before screening around the world. Crossing Rachmaninoff followed a single protagonist, Italian-born Auckland pianist Flavio Villani so Tansley wanted to find out how more collaborative performing arts works get made.
"These days, you can look on YouTube and there are tonnes behind-the-scenes videos, like little clips backstage where it's sort of a glimpse of things, but what I hope, what I'm aiming for, is something that gives a sense of what it's actually like to be doing it yourself rather than just being a bystander," she says.
"Dance is such an ephemeral art-form. You're creating art in the moment out of people's bodies within space and I'm interested in how that process works. To me, that's a kind of alchemy."
It's a far cry from the days when her own daughter did ballet. Tansley describes herself as "not a very good ballet mother" who could never get hair buns quite right — "they were always kind of scrappy and slightly off centre" — but she's now getting a new appreciation for what dancers do.
"Everyone knows dancers have incredible bodies and that they're athletes, but they also have incredible brains in that they can pick up steps virtually after one run-through and then, on top of that, they might go into another studio for the next session and rehearse a completely different ballet," Tansley says.
"They're not just working on one ballet at the same time, necessarily. They can learn and remember steps — and maybe it's a ballet they performed several years ago — but the body memory just comes back. I find it absolutely fascinating."