If you haven’t seen Kong: Skull Island, you should, it’s a blast. It follows a group of explorers who venture out into an island but end up finding monstrous creates, including a 100-foot tall gigantic ape. Wben you first meet Kong, it’s a sight to behold, and creating this awe required a lot of hard work from CGI-specialists Industrial Light and Magic.

The studio responsible for some of the most iconic CGI work ever—Jurassic Park, Indiana Jones, Star Wars—went to great lengths to create an authentic design that fits his history, that of an ape that has lived unkempt on an island battling creatures for years.

ILM worked closely with director Jordan Vogt-Roberts to create the ape’s look. He wanted to borrow elements from the original 1933 King Kong design as well as real-life San Francisco Zoo gorillas that were studied. Most of the attention went to the head and the face to create a human-like design people could empathize with.

In the movie, there are specific moments that call for an emotional connection with Kong, and since he doesn’t speak, it had to be done through his eyes and facial expressions.

Extra attention was put into crafting Kong’s fur. His matted, entwined and unkempt fur required keeping track of over 17 million hairs. That goes on top of the twigs, leaves, and mud used to make it look even dirtier.

The end result was a stunning design that truly comes to life the movie.

You can see ILM’s comprehensive breakdown of all the visual effects work in the video above.