The show centers on FBI special agents Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson) who work on cases linked to the paranormal, called X-files.

"Redux II" continues immediately afterwards with Scully hospitalized, and Mulder is offered a deal to ally with the Cigarette Smoking Man (William B. Davis).

Professor Arlinsky, the team's leader, sends ice core samples containing presumably alien DNA to Fox Mulder (David Duchovny).

Mulder, spotting a small hole in his ceiling, rushes upstairs, bursts into the apartment above his, and kills government employee Scott Ostelhoff.

Scully falsely identifies the body and is met by Assistant Director Walter Skinner (Mitch Pileggi), who tells her that Section Chief Scott Blevins (Charles Cioffi) is looking for her.

As Mulder breaks into the Department of Defense, the Smoking Man (William B. Davis) searches his apartment, believing he is not dead.

Scully explains to the FBI panel that Mulder was a victim of an elaborate conspiracy and that she was given a fatal disease by someone in the room.

Meanwhile, the Smoking Man tries to convince the First Elder (Don S. Williams) that Mulder will join their side if he is given a good reason to do so.

As he is leaving, he meets with the Smoking Man, who claims that he can cure Scully by using a chip inside Mulder's stolen vial.

While the writers kept "playing" with the idea of Mulder's loss of faith, executive producer Frank Spotnitz admits that fans never seemed to accept this turn of events and they refused to see the Cigarette Smoking Man victorious.

According to executive producer Frank Spotnitz, "Redux" posits a number of reasons for Scully's recovery, including standard medical treatment, divine intervention engendered by faith, or the chip that the Cigarette Smoking Man offers up.

A clear-cut answer is never really provided, which John Shiban claims was intentional, as they wanted to leave it open to interpretation.

[5] According to R. W. Goodwin (the director of "Redux"), the production crew was so impressed by actor John Finn's monologue claiming that UFOs are a government hoax that he received a round of applause after finishing his takes.

[7] The original versions of the "Redux" script featured "Gray-Haired Man" (played by Morris Panych) in the place of "Quiet Willy".

However, when Panych was unable to appear in the episode due to scheduling issues, the story was re-written and the new character was created, portrayed by Willy Ross (né Steve Allen).

[9] Likewise, Spotnitz called "Redux II" "one of [his] favorite episodes" and explained, "I think the story has a crystal purity and clarity, and it just comes to a perfect point for me".

[12] Part of the reason "Redux" was so widely viewed was because the show's previous episode, "Gethsemane", had created speculation about whether or not Mulder was actually dead.

[14] VanDerWerff noted that the idea that Mulder had killed himself was not effective, because the show's audience knew that a movie had been scheduled for release in the summer of 1998.

"[15] Furthermore, Vitaris criticized several plot holes in the episode, including Mulder's easy entrance into the Department of Defense and the character's antics, such as his attack on Ostelhoff.

However, despite the overall negative review, Vitaris did mention that, "There's only one truly galvanizing scene, as that's the confrontation between Scully and Skinner after he follows her to the lab where she is performing her DNA test.

"[15] Robert Shearman and Lars Pearson, in their book Wanting to Believe: A Critical Guide to The X-Files, Millennium & The Lone Gunmen, rated the episode one star out of five.

The two heavily criticized the "Skinner-as-traitor" plot, noting sardonically that "the production team aren't going to do [reveal he is the antagonist], and the shock 'villain in the room' reveal will be Section Chief Blevins–a character so important in the framework of the series that, barring his appearance in the Season Four finale, we haven't seen him in ninety-four episodes.

In his critique of "Redux", he noted "While many people don't care for 'Redux', I think it does a good job of preparing us for the second hour (although, it invalidates Gillian's emotional context from the S4 finale).

Club awarded the episode an "A" rating and noted that "whatever reservations I may have over a three-episode story arc, this final entry does a good job of re-investing us in the show's basic ideals, returning us to a rough form of the status quo in a way that's exciting, emotionally powerful, and satisfying despite only incremental forward momentum".