A video has been posted by the late Stan Winston School of Character Arts, and it shows the creation of the Chestbuster alien from James Cameron’s awesome sequel Aliens.
No sequel to ALIEN would have been complete without paying homage to the infamous ‘Chestburster’ scene, so director James Cameron memorably included the grotesque parasites in ALIENS as well.
H.R. Giger’s design remained practically unchanged by the Alien FX team at Stan Winston Studio apart from adding two tiny arms to create consistency between it and the anatomy of a full grown Alien Warrior. Cameron and Stan Winston decided that the addition of arms also made sense on a purely functional level, allowing the chestburster to pull itself free from its victim’s chest.
The chestburster makes its first appearance in ALIENS during a nightmare sequence. Ripley (Sigourney Weaver), suffering from post-traumatic stress caused by her near death ordeal aboard the Nostromo, dreams of a chestburster pushing its way through her ribcage as the Weyland-Yutani medical staff restrain her.
The chestburster reappears later in the film when Ripley and the military team finally locate the missing colonists of LV-426, who have all been cocooned for use as xenomorph incubators in the alien nest. One colonist, barely clinging to life, begs our heroes to kill her. Moments later, a chestburster explodes through her sternum and the commandos burn it with their flamethrowers.
To achieve the effect, Winston and his crew created two chestburster puppets. The first was built to be tough. as it needed to be able to rip through Coles’ artificial foam latex chest multiple times. The second, “post-burst” puppet didn’t have to withstand the same abuse and so it featured a more delicate cable-controlled mechanism that allowed a wide-range of fluid motion.