Spoilers
“Firewalker”

Mulder and Scully are out of a mission for the first time since Scully returned from her kidnapping and near death experience.
This felt very much like the first season episode “Ice” just set in a different location.
That is not necessarily a bad thing since “Ice” is one of my favorite episodes from season one. Still, the repetition of the basic structure feels a little lazy.
However, there were some cool effects, including the bulging neck that are shown by those infected. It was really creepy.
“Firewalker” was watchable and it works as a monster-of-the-week episode that can bring Mulder and Scully back to the field.
Otherwise, at best, okay episode.