 However, Subject 20 mutates rapidly and uncontrollably and kills all of the laboratory subject animals before cocooning itself within an examination booth.After Subject 20 hatches from its cocoon, it begins killing the personnel at the station, starting with the lab tech charged with cleansing the subject lab of the dead animal test subjects.Professional troubleshooter Mike Colby, accompanied by his robot assistant SAM-104, is called in to investigate the problem.