When the first trailer for the big screen adaptation of the long-running Broadway musical Cats debuted over the summer, it became the talk of the web, but not for any good reason. Much of the internet was lambasting the movie for having some nightmare-inducing visual effects used to bring the digitally enhanced cat people to life. While it didn’t result in a complete overhaul of the character designs like Sonic the Hedgehog, director Tom Hooper reveals that it did help them figure out some changes that needed to be made to the Cats visual effects in as post-production continued.

First of all, Empire asked Tom Hooper about the mostly negative reaction that Cats got when the first trailer dropped. Hooper was very much aware, but it doesn’t seem like it shook him. The director said:

“I was just so fascinated because I didn’t think it was controversial at all. So it was quite entertaining. Cats was apparently the number-one trending topic in the world, for a good few hours at least.”

I’m not sure anyone thought the Cats trailer and the character designs were controversial. But it certainly awakened some horrors in people’s minds as they watched cat hybrid versions of Francesca Hayward, Jennifer Hudson, Taylor Swift, Idris Elba, James Corden, Rebel Wilson, Ian McKellen, Judi Dench, and Jason Derulo prancing around.

The good news is that the reaction did help Hooper and his crew take a closer look at the visual effects to see what could be changed in order to make the cats a little easier to swallow. Hooper explained:

“We’d only finished shooting in March, so all the visual effects [in the trailer] were at quite an early stage. Possibly there were, in the extremity in some of the responses, some clues in how to keep evolving [the production]. When you watch the finished film, you’ll see that some of the designs of the cats have moved on since then, and certainly our understanding of how to use the technology to make them work has gone up, too.”

So while they didn’t take all of the negative criticism to heart after the movie came out, perhaps Hooper and the crew realized that something needed to be done in order to make it easier to accept these cats as characters rather than science experiments gone terribly wrong.

Judging by the most recently released trailer, it doesn’t seem like those changes have been revealed just yet, especially since Hooper says that we’ll see these changes in the finished film. We know the crew is working right up until the last possible minute in order to meet awards deadlines for the Golden Globes and other voting bodies, so it only makes sense that we haven’t seen the finished visual effects yet. Hopefully they look better than what we’ve seen so far.

Cats is slated to pounce into theaters on December 20, 2019.