More than 30 years ago, Carrie Henn was a 9-year-old living in London, where she'd just landed a big role in what would become one of the greatest sci-fi films of all time: James Cameron's Aliens. In the 1986 smash, Henn starred as Newt, the soot-faced, wide-eyed orphan whose family has been wiped out by xenomorphs, and who develops a near-familial bond with Ripley, the creature-cratering heroine played by Sigourney Weaver. And if you thought that hanging around the set filled with multi-mouthed monsters (not to mention James Cameron) was scary for a young kid, you're right—though, as it turns out, Hehn's fears had nothing to do with her acid-drooling co-stars.

"I wasn’t nervous about being on set, because I knew everybody, and they were very friendly," Henn said during a recent stop at the WIRED Cafe during Comic-Con International, where the film is celebrating its 30th anniversary. "The aliens were all my friends, wearing suits. I was actually most nervous about going to the cafeteria for lunch, because I had to go in-character as Newt, and I thought everybody would be staring at me. I didn’t have any concept that everybody else was going to be dressed up, too. My tutor actually gave me a big pair of sunglasses to wear when I went in. But it turned out not to be such a big thing."

Henn had gotten the part after a meeting with Weaver, who'd flown on the Concorde to London to test out their on-screen chemistry. "I was excited, because I was like, “She was in Ghostbusters! How cool is this?”, Henn remembered. The slow-building Newt-Ripley relationship—they start off skeptical of one another, but eventually develop a de facto mother-daughter bond—has always been the heart of Aliens, culminating in the film's most famous moment, in when Ripley, having finally tracked down the abducted Newt, confronts the Queen alien-turned-kidnapper and delivers one of the most delightfully bitchy lines in movie history.

According to Henn, who still keeps in touch with Weaver, the two actress' bond was evident from the get-go. "Immediately, we hit it off," she said. "She took me under her wings when we were filming, because I was so inexperienced. I can't describe my relationship with her, because she’s more than just a friend—what you see on screen is genuinely how we feel about each other."

Even though Henn was only 10 when Aliens was released, she has a vivid recall of her days on the set. Her favorite scene to shoot? The one in which Newt, stuck chest-high in water, is snatched up by a towering alien—a terrifying sequence, and one that gave most other 10-year-olds nightmares for years to come. But for Henn, it was mostly a chance to goof around. "The first assistant director had actually had someone stay there overnight, to make sure the water stayed warm," she said. "But it was actually too warm for me, so I would sit up on bars on the side, and the alien and I would stay up there, kicking our feet in the water."

Aliens would prove to be Henn's only major acting role: By the time the film was released, she and her family had moved back to the United States, and she soon decided to pursue a career in education (she now teaches fourth grade in Northern California; occasionally, one of her students will bring in an Aliens DVD for her to sign). But she still finds time to visit conventions, and this spring, in celebration of Aliens Day, she watched the movie for the first time in nearly a decade. "It’s very weird, because I have a daughter who’s now the age I was when I made the movie, and she’s like my clone," Henn said. "So as I’m watching it, it’s like watching my daughter up there." Newt, there it is!