The crews work to contain a dangerous forest fire and save a group of environmentalists protesting a housing development.
Mulder and Scully track a legendary creature that has roamed the New Jersey countryside for over forty years.
Mulder and Scully are stalked by a deadly new life form that has invaded the bodies of a volcanic research team.
When Dr. Fredrick Walden (recurring guest star Rob LaBelle), the famed linguist who was injured while studying the caves, awakens suddenly from a coma, he possesses fantastic powers and goes on a dangerous mission. Meanwhile, Lana helps Clark celebrate his "birthday" in a very special way. Lex and Helen endure doubts and stress while planning their wedding. And Lionel forges a surprising alliance with Chloe.
In Summer 1999, Megan wants to be adventurous and makes fake IDs for the gang. In Winter 1999, a burst pipe leads the Landrys and Isabella to a messy night at the Chambers house. Isabella wants to help but is met with resistance from Megan.
