Terry asked the Coen brothers about casting and filming the cat in their film Inside Llewyn Davis:
Ethan: We used the advice of the cat trainer, the animal trainer [to get] a kind of orange, marmalade tabby cat just because they’re common, so easy to double, triple, quadruple, there were many cats playing the one cat. It comes across pretty well in the movie, but the whole exercise of shooting a cat is pretty nightmarish because they don’t care about anything. They don’t want to do what you want them to do. As the animal trainer said to us, “A Dog wants to please you. A cat only wants to please itself.” It was just long, painstaking, frustrating days shooting the cat.
Joel: What you have to do is basically find the cat that’s predisposed to doing whatever particular piece of action it is that you have to film. So you find the cat that isn’t afraid to run down a fire escape or the cat that’s very docile and will let the actor just hold them for extended periods of time without being fidgety. Then you want the fidgety cat, the squirrely cat for when you want the cat to run away. And you keep just swapping them out depending on what the task at hand is.
Ethan: In True Grit we had a vulture, a trained vulture… that was a pain and that was even, by vulture standards probably a stupid vulture and that was frustrating. But I would take a vulture over a cat. The cat was just horrible.