Sheriff Valenti is suspended from the force after refusing to answer the FBI's questions about Max and Isabel, but he soon finds himself right back in the thick of things when Laurie DuPree shows up at his house claiming to be chased by aliens.

Michael and Maria flee from Roswell after helping Laurie DuPree escape from the police, and Max learns that a deadly parasite was released into Earth's atmosphere when their ship crashed 50 years ago.

Max tries to stop Alex and Kyle from being buried alive in a cave filled with glowing blue crystals; Isabel is kidnapped by Grant Sorenson possessed by the alien parasite queen; Michael is shot while trying to protect Laurie.