Ultimately this one didn't get picked up but in prepping the pitch I did a number of tests with facial motion capture using my own face. There are a lot of different ways to do this now, but I used Cinema 4D for this. The process is a bit complicated but goes a little something like so: record your face and map the different expressions to your target (the fish in the case) using pose morphs. It's a powerful and quite flexible system that I hope to use again in the future.