One word: paranoia.

Even before Mulder and Scully get started with their investigation, the agent’s identities are being questioned, but this is just a taste of things to come. Throughout the episode, things break down to the point that even the agents are unsure about one another. The suspicion between the two becomes more intense throughout the installment culminating with Mulder being locked up. But is he the one infected?

The episode is heavily influenced by John Carpenter's The Thing, and the crew did an excellent job at recreating the feeling of isolation and fear from that film. I feel there is a lot this episode can say about our current environment. Suspicion is everywhere these days to the point where friends and family are sometimes pitted against each other for various reasons. Very good episode and very relevant.

Disturbing Moment: Creepy worms burrowing around underneath people’s skin. Enough said!