When you’re the only human on an island in the middle of an ocean, you have to learn to take care of yourself. In The Last Jedi, we see Luke Skywalker do so by using the natural resources on Ahch-To. He catches fish, he probably roasts porgs (I’m just being realistic), and he squeezes green milk from the thala-siren. The vivid scene isn’t gross to anyone who’s been on a dairy farm, but it caught Rey and some fans off guard. We asked creature shop head Neal Scanlan about bringing the scene to life, and he told us it’s all practical…and involved a helicopter.

“At the very beginning of the film, Rian [Johnson] said to me that he wanted to take animatronics and practical effects and put them there on a real location—he didn’t want to do certain things in the studio,” Scanlan explained. “We went to that location, we photographed that location, and we created a digital map of it so that later back at Pinewood we could recreate the rocks. When we sculpted the thala-siren—she’s a full-sized animatronic puppet and she’s about 18 feet tall—she was sculpted to fit into the rocks so that she actually looked like she was sitting in that environment.”

They created the entire puppet at Pinewood from foam latex. The thala-siren has a mechanism on the inside so her head could tilt forward “like a submarine hatch.” Scanlan said that allowed two puppeteers to get inside the creature—one in the front and one above him. “One would operate the shoulders and the flippers at the top and the other person would operate the belly and the milking mechanism or the udder mechanism at the bottom,” he said.

Getting the large puppet to Ireland was no small task. They had to transport it to location by helicopter. “It’s the only creature I’ve ever flown by helicopter,” Scanlan laughed. Once there, they got the puppeteers inside and staged two other smaller thala-sirens in the background. “We had two puppeteers on the outside, one did the head from a rocky position at the top—he had the head on a rod—and there were two other puppeteers at the bottom that did the bottom flippers,” Scanlan said. “There were the only three other people on the set, and then Mark [Hamill] and Daisy [Ridley] came and acted out the scene. And when Mark, as you know, wanted delivery of the milk from the udder, then the puppeteer on the inside duly obliged.”

Did the milking scene squick you out to the point you had to look away like Rey? Share your reaction to the thala siren in the comments.

Images: Lucasfilm/Disney

Amy Ratcliffe is an Associate Editor for Nerdist. She likes Star Wars a little. Follow her on Twitter.

Read more about The Last Jedi!

• Kelly Marie Tran’s The Last Jedi audition.
• How porg sounds were made.
• How The Last Jedi fails to hold Poe Dameron accountable.