Cameron designed the alien queen and worked with Winston on several concepts, including large puppets, miniatures, and costumes with several people inside. A frame was built large enough to hold two people, covered in black polythene bags, and hung on a crane. The prototype was a success, and Cameron wrote the alien-queen scene. The final alien queen was a puppet made of lightweight polyurethane foam. Two people sat inside to control the arms; the legs were controlled by rods connected at the ankles, and a separate person whipped the tail around with fishing line. The head was manipulated with a combination of servomotors and hydraulics controlled by up to four people. The effect was hidden by lighting, steam, slime, and smoke.