When the Government funded Arctic Ice Core Project's final transmission is a crazed geophysicist saying, "We are not who we are", Mulder and Scully join the team sent to investigate. Along with geologist Dr. Denny Murphy, physician Doctor Lawrence Hodge, toxicologist Doctor Nancy Da Silva and their pilot Bear they travel to Icy Cape, Alaska.
On arrival at the Arctic base they discover that the geophysicists all killed themselves or each other. The Ice Core Project's mission was to drill in to the Arctic ice and extract core samples to analyse Earth's climate all the way back to the dawn of man. Further investigation reveals that there was a pathogen in the latest ice core samples recovered. It appears that this pathogen got loose among the geophysicists and that it is capable of inducing a killing frenzy in it's host. When the discovery of an infected dog which attacks the group leads to the pilot Bear being infected, Scully orders a quarantine to prevent the pathogen spreading. But Bear refuses to stay and has to be restrained as he attempts to leave, during the scuffle something is seen under his skin, it is surgically extracts and turns out to be some sort of parasitic worm.
The location that the ice core sample came from is traced to a meteor buried deep in the ice indicating the possibility that the organism is alien in origin. With the possibility that other members of the group could be infected it soon becomes apparent that the first thing to die is trust.
Episode Number: 8
Season Number: 1
First Aired: Friday November 5, 1993
Production Code: 1X07