A team varied between Scully and Mulder, two other scientists, a pilot, and the guy who plays Bana on Seinfeld, go up to an Arctic research post where all members have died off by either killing each other or killing themselves. They discover there's a worm- a virus- that is parasitic to the point of madness and death. The problem is, after a certain dog lashes out, anyone could be infected, but who? This is not just my favorite episode of season 1, but also one of my favorites from the show. The Arctic environment encloses the characters and, of course like Carpenter's the Thing, it's a lot of fun watching these even-tempered characters suddenly start to flip out in dramatic scenes. And the visual effects of the worm and its effects under the skin are cheesy, I didn't mind them at all. The drama between the characters ends up working more than it would usually because of the tension and because all of the actors (including the Bana guy) understand what's going on in the story. And, as usual, I loved the ambiguity of the ending. Highly recommended.