After Major Graffa is possessed by the alien meteor found buried beneath Roetem Towers, Captain Weldon steals the meteor fragment that landed at Butler's farm and goes AWOL. She kidnaps Brogan to enlist his help in recovering the meteor from Graffa, but Carson learns that the meteor is a parasitic alien seed and the meteor fragment is a spore to fertilise it – bringing them together will destroy all life on Altor!