Queen Alien was played by Stuart St Paul and Malcolm Weaver, the only two James Cameron would have inside his queen. The actual Queen was built around them, strapped back-to-back. Their neck muscles together swung its head, their feet worked a paddle to swing the tail, the outstretched arms formed the upper arm, and wrists became the elbow joint puppeteering a floppy hand on (4, 2 each) sticks that were rested on a stand. They had earpieces and took direction direct from James Cameron and worked with Sigourney Weaver (no relation to Malcolm) in the big end fight. They were strapped in at the beginning of the day, taken out for lunch, and then not until the end of the day. Comfort breaks were very rarely taken because of the assembly time.
This feature-length documentary is featured in the DVD set 'The Alien Quadrilogy' and on the 2-disc DVD for Aliens (1986).
Included as a multi-part special feature on the Making of the Alien Anthology disc in the Alien Anthology blu-ray box set, released in 2013.