WARNING: The following article contains spoilers for Captain Marvel, in theaters now.


Goose, the cute orange feline stealing hearts throughout Captain Marvel, turned out to have quite a secret identity: he was an alien Flerken, capable of releasing enormous tentacles that sent Skrulls running in fear. In reality, he was played by four ordinary Earth cats (Reggie, Gonzo, Archie and Rizzo), who all had a difficult time adapting to the Skrull costumes.

When asked if anything caused difficulty for the cats, animal trainer Ursula Brauner of Boone’s Animals for Hollywood told Vulture, "I think maybe it was probably the Skrull costumes. That was one of our challenges because they look so different from people. Ben Mendelsohn was so amazing getting the cats used to the costume and makeup, though. He showed them how he moved and sounded, and he was just really great getting the cats to like him."

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Brauner recounted shooting a certain scene in the tight confines of the quad-jet set, noting that Mendelsohn didn't look remotely human while in his Skrull costume. The cat actor Reggie, who has more screen time than the rest of the cats combined, needed to adjust to the unfamiliar creature sharing the scene with him. "Reggie was a little unfurled," said Brauner. "[Captain Marvel directors Anna Boden and Ryan Fleck] took the time to say, 'Let’s stop what we’re doing and get the cat comfortable.' We had Reggie sitting on a chair, and Ben was sitting in the chair next to him, and we let Reggie go to him and explore on his own volition, and pretty soon, he realized Ben was just like us, but he just looked different."

Animal lovers will be glad to hear the cat actors in Captain Marvel were not only kept safe from alien menaces, but also trained in a way that respected their natural behavior and kept them relaxed in potentially stressful situations. As Brauner explained, "The most important thing for the animals — and this is the most important part of what we do — our philosophy in training is to build a trust and a bond with any of our animals. So much of what we do in the preproduction and training was getting them comfortable to be in that environment, so they feel calm and safe and concentrate on the job at hand."

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Directed by Anna Boden and Ryan Fleck, Captain Marvel stars Brie Larson as Carol Danvers, Samuel L. Jackson as Nick Fury, Jude Law as the commander of Starforce, Clark Gregg as Phil Coulson, Lee Pace as Ronan the Accuser, Djimon Hounsou as Korath the Pursuer, Gemma Chan as Minn-Erva, Ben Mendelsohn as Talos, Lashana Lynch as Maria Rambeau, Algenis Perez Soto as Att-Lass, McKenna Grace as a young Carol Danvers and Annette Bening as the Supreme Intelligence.