A test pilot who may have been flying aircraft made with alien technology disappears, and Mulder and Scully must defy their own government to find the truth.
Michael's medical condition forces him to go to the hospital; Lincoln and Sucre get into an explosive situation; Agent Self meets with a shocking ally.
Michael, Lincoln and Sucre have to crash a police benefit to get the next card key; Sarah falls back into an old habit; on his first day of his new job, T-Bag runs into some old friends and arouses suspicion.
Shirley Schmidt reluctantly enlists Denny Crane's help to defend a congressman being sued for failure to keep a campaign promise.
Michael and the team have a day to find the next cardholder or they risk going back to prison; Mahone seeks revenge on Wyatt, who is attempting to get information on Sara's whereabouts; T-Bag finds a new identity and gets a job offer.