Click on the episode for artwork from 201 Days of the X-Files


Season One

Season Two

Season Three

Season Four

Season Five

Season Six

Season Seven

Season Eight

Season Nine

Season Ten

Episode #/Title

Plot Synopsis

Adaptations and Reprints

Continuity Notes



Comic: X-Files: Year Zero #1-3 (flashback only) (IDW)

Trade pb: X-Files: Year Zero (IDW)

Flashback only. The frame story is set during Season 10.

First appearance of Mr. Xero (later Mr. Zero), whose tips help establish the existence of an X-Files division in the FBI, as worked by Bing Ellinson and Millie Ohio.


Comic: X-Files: X-Mas Special: Merry Christmas, Comrade (IDW)

A tale of Bing Ellinson and Millie Ohio, the X-Files team of the 1940s, who face a deadly gremlin and a lost love-on Christmas Eve.

Flashback: December 1943.



Comic: X-Files: Year Zero #4-5 (flashback only) (IDW)

Trade pb: X-Files: Year Zero (IDW)

Flashback only. The frame story is set during Season 10.




Twin Peaks

Seasons 1-2, Fire Walk with Me & the Missing Pieces

Although there is no direct connection between the two shows, the series Fringe connects The X-Files to Twin Peaks, putting all three in the same universe. Fringe not only mentions a promising FBI agent named Mulder, who went off the rails, but features Doctor Jacoby's two-color glasses and says "they were sent to be by a Doctor Jacoby from Washington State."

David Duchovny, who plays FBI agent Fox Mulder  on the X-Files, played FBI agent Denise Bryson on Twin Peaks. She is transgender and once went by the name Dennis Bryson. She worked with Dale Cooper in 1987, went undercover for the DEA in 1988, and met with Cooper again in 1989. In 2014, she became the FBI Chief of Staff.

February to March 1989


Season 5: Episode 3

5x01 Unusual Suspects

In an important chunk of X-Files pre-history, up-and-coming FBI agent Mulder crosses paths with an unlikely trio of eccentrics (The Lone Gunmen); pursues a beautiful alleged terrorist; and gets a searing glimpse into his own future.  First appearance of Susanne Modeski.  X appears. First appearance of Detective John Munch.


Origin of the Lone Gunmen and Mulder's involvement with them.


Detective John Munch makes his first chronological appearance here. The character's first real-world appearance was in the series Homicide: Life on the Street, which this episode crosses over into, bringing that series (and a few others) into the same universe as The X-Files. See that entry for more details.



Season 5: Episode 15

5x15 Travelers

One year before reopening the X-Files, young agent Mulder investigates a bizarre murder.  The answers he seeks lie in the not-so-distant past: during the Red Scare of the 1950's.  First appearance of Agent Arthur Dales.


Internal dates provided.  Flashback portion begins 6/24/52.


Agent Arthur Dales was unaware of the earlier X-Files cases dating to the late 1940's.

11/21/90 – 11/22/90


Short Story: "Sewers"

From the book: The X-Files: Trust No One (IDW)

Flashback: 11/63



Comic: X-Files #35: N.D.E. (pt. 1) (flashback only) (Topps)


Flashback only (shown in b&w). Year is based on date shown on pilot (1992). I've changed it to reflect the changed premise (see below)

3/5/93 – 3/6/93


Season 1: Episode 1

1x79 Pilot

FBI Agent Dana Scully is paired with maverick agent Fox Mulder, who has made it his life's work to explore unexplained phenomena.  The two are dispatched to investigate the mysterious deaths of a number of high school classmates.  Cigarette Smoking Man is introduced.  Section Chief Scott Blevins is introduced. The serial killer Monty Props is first mentioned as having been caught by Mulder in 1988.


Book: #1: X Marks the Spot (Harper, 1995)

Book: The X-Files Collection (Voyager, 1997)

Comic: Season One: Pilot (Topps)

Comic: #0a & 0b Special Collector’s Item (Topps)

Comic:  Special Edition #1 (Topps)

Comic: Special Ashcan Edition (Topps)

Trade pb: The X-Files Volume 1 (Checker)

Hardcover: The X-Files Classics: Season One: Volume 1 (IDW)

Internal dates provided.


Despite the year provided, the CD-Rom Unauthorized Access (UA) and several episodes (4x05, 4x07) which seem to confirm the 1992 date, the end of Season 4, opening of Season 5, Season 9 and Season 10, as well as other evidence strongly suggests a 1993 date. See my introduction for more information on this discrepancy.

3/6/93 – 3/22/93



Novel: Goblins (Harper, 1994)


Book Reprint: The X-Files: Goblin, Whirlwind (Quality Paperback Book Club)

Book Reprint: The X-Files Archives: Volume 1: Whirlwind and Ruins (IDW, 2015)

Month and day indicated in text.  This must be in 1993 despite other evidence to the contrary (which makes Mulder right when he says the 5th is Wednesday, not the narrative which says Thursday). It cannot be May 5th '94 as Episode 1x23 begins on 5/8/94 and the X-Files are not shut down until the 25th

5/5/93 – 5/9/93


Season 1: Episode 3

1x02 Squeeze

Mulder and Scully try to stop a mutant killer, Eugene Tooms, who can gain access through even the smallest of spaces and awakens from hibernation every 30 years to commit murder.  Tooms appears again in Season I, Episode 1x20: "Tooms."


Book: #4: Squeeze (Harper, 1995)

Book: The X-Files Collection (Voyager, 1997)

Comic: Season One: Squeeze (Topps)

Trade pb: The X-Files Volume 1 (Checker)

Hardcover: The X-Files Classics: Season One: Volume 1 (IDW)

Internal date provided on computer screen.

7/20/93 – 7/28/93


Season 1: Episode 2

1x01 Deep Throat

Acting on a tip from an inside source (Deep Throat), Mulder and Scully travel to Idaho to investigate the unusual disappearances of army test pilots.  Inexplicably, one of the missing pilots shows up, but his wife insists he's different.  Mulder takes off alone to explore the secret air base, but after spotting a UFO, he is caught and injected with drugs.  Determined to get him back, Scully takes one of the security men hostage and goes to the base, where Mulder is brought to her.  He has lost all memory of what he has seen or even how he got there, however.


Comic: Season One: Deep Throat (Topps)

Hardcover: The X-Files Classics: Season One: Volume 1 (IDW)

Close inspection of FBI file (UA) indicates 8/93. 

8/16/93 – 8/18/93


Season 1: Episode 4

1x03 Conduit

A teenage girl is abducted by aliens, compelling Mulder to confront feelings about his own sister's disappearance.


Comic: Season One: Conduit (Topps)

Hardcover: The X-Files Classics: Season One: Volume 1 (IDW)

The original FBI file dates as shown for Mulder & Samantha are erroneous and have been superseded by later information. Internal date taken from fax machine report.

8/25/93 – 8/29/93


Season 1: Episode 5

1x04 The Jersey Devil

 Mulder and Scully investigate murders thought to be the work of a legendary man-beast living in the New Jersey Woods.

Toe tag states death date @ 8/29/93. The investigation begins Friday (Mulder is locked up for the weekend). The Jersey Devil's DOD is 9/23/93 (as seen in UA).

9/17/93 – 9/23/93

Epilogue: 9/25/93


Season 1: Episode 6

1x05 Shadows

Mulder and Scully investigate unusual murders committed by an unseen spectral force protecting a young woman.


Book: X-Files #15: Haunted (Harper, 1995)

Comic: Season One: Shadows (Topps)

Hardcover: The X-Files Classics: Season One: Volume 2 (IDW)

Date on video footage of ATM display. Continuity error in the gravestone of Howard Graves dated October 5 (he died 8/18)

9/25/93 – 9/30/93


Season 1: Episode 12

1x11 Fire

Mulder and Scully encounter a disturbed murderer who can start fires with the touch of his hand.  Mulder is visited by an old flame from his days at Oxford, Phoebe Green, who is trying to protect a wealthy British family vacationing in Massachusetts.  But the assassin, who has been killing members of Parliament, has murdered the estate's caretaker and taken his place.


Comic: Season One: Fire (Topps)

Trade pb: The X-Files Volume 3 (Checker)

Hardcover: The X-Files Classics: Season One: Volume 2 (IDW)

According to a fax Scully receives on day 4 of the episode, the date is 10/05/93. Day 1, however, must be a weekday – as they are in court.

10/1/93 – 10/6/93


Season 1: Episode 9

1x08 Space

A mysterious force is sabotaging the United States' space shuttle program and Scully and Mulder must stop it before the next launch.  But Lt. Col. Belt, supervisor of the shuttle program, is having flashbacks to a mysterious event on a former mission, and appears to be the one  behind the sabotage.


Comic: Season One: Space (Topps)

Hardcover: The X-Files Classics: Season One: Volume 2 (IDW)

No specific dates indicated. Dates given are speculative.

10/8/93 – 10/13/93


Season 1: Episode 10

1x09 Fallen Angel

 Scully and Mulder investigate a possible UFO crash site, which Mulder believes the government is covering up.  First appearance of Max Fenig (who returns in Season 4, episode 4x17: Tempus Fugit).

No specific dates indicated. Dates given are speculative.

10/17/93 – 10/20/93


Season 1: Episode 7

1x06 Ghost in the  Machine

When an advanced computer with artificial intelligence begins killing in a prestigious office building in order to preserve its existence, its creator decides he must destroy rather than allow it to get into the government's hands.  Mulder's former partner, Jerry Lamana, is introduced, and becomes one of the computer's victims.


Book: #11: Ghost in the Machine (Harper, 1995)

Scully types her report on what is likely Day 3 that is 10/24 (which is a Sunday)

10/21/93 –10/29/93


Season 1: Episode 11

1x10 Eve

Two bizarre, matching murders occur simultaneously on different coasts, each involving a strange  young girl who is identical to one another.  Both families were involved a Dr. Sally Kendrick, who was fired from the clinic for experimentations in eugenics.  Deep Throat tells Mulder of a top secret eugenics program that created identical boys and girls.  Mulder and Scully discover one in a home for the criminally insane, and she is the exact duplicate of Sally Kendrick.


Book: #2: Eve (Harper, 1997)

Book indicates early November.  1st murder on a Saturday (which is the 6th). 

11/7/93 – 11/9/93


Season 1: Episode 8

1x07 Ice


Mulder and Scully and a small party head to the Antarctic to discover the truth behind the deaths of a research team on assignment there.  Once there, their pilot becomes infected with a deadly organism of unknown origin which causes its victims to become violent.  After his death, the party are trapped and begin to suspect one another of being infected.


Comic: Season One: Ice (Topps)

Trade pb: The X-Files Volume 3 (Checker)

Hardcover: The X-Files Classics: Season One: Volume 1 (IDW)

Transmission dated 11/5/93.  As their arrival is on a Wednesday, it must be the 11/10.  (which sets the events after the show aired!  See introduction for further info)

11/10/93 – 11/13/93


Season 1: Episode 20

1x19 Darkness Falls

When loggers in a remote Pacific Northwest forest mysteriously disappear, Mulder and Scully are called in to investigate.  Together with a forest ranger, the security chief for the logging company and an eco-terrorist, Mulder and Scully find themselves trapped in the forest where they must escape nightfall, or else...


Book: #2: Darkness Falls (Harper, 1995)

Book: The X-Files Collection (Voyager, 1997)

No specific dates indicated. Dates given are speculative, based on start of logging season. Mulder and Scully hospitalized.

 11/29/93 – 12/6/93


Season 1: Episode 15

1x14 Lazarus

 When an FBI agent, Jack Willis, and a bank robber are both shot during a botched bank heist, the robber is killed but the agent begins to take on the criminal's persona.  Willis, Scully's former  instructor and boyfriend, begins to progressively behave in strange ways, leading Scully to attempt to aid him by tracking down the bank robber's former girlfriend.  Scully is abducted (her first of  many) by Willis and the girlfriend who begins to think that perhaps Willis is in fact her dead lover.

Scully states she is born on 2/23/64.  She tells Mulder that the b'day card he gives her is two months early.  An auto-requisition form confirms the month and year.

12/21/93 – 12/26/93


Season 1: Episode 13

1x12 Beyond the Sea


Against Scully's better judgment, Mulder seeks the aid of a death row inmate, Luther Lee Boggs,  who claims he has psychic abilities, to help them stop a killer who's on the loose.  Boggs fails Mulder's test, but the inmate ensnares Scully with his seeming ability to conjure up the spirit of Scully's father who has recently died.  Contrary to Mulder's warnings, Scully falls deeper into Bogg's trap.  First appearance of Scully's parents: Captain William Scully and Margaret Scully.


Comic: Season One: Beyond the Sea (Topps)

Hardcover: The X-Files Classics: Season One: Volume 2 (IDW)

Scully's father dies. Mulder is shot.  Dates are speculative (Scully's father chides her about Christmas decorations still up after Boxing Day).

12/31/93 – 1/7/94 


Season 1: Episode 14

1x13 Gender Bender

 Mulder and Scully seek answers to a bizarre series of murders committed by a person who appears to kill as both male and female.  Clues lead the agents to a rural area of Massachusetts where the  Kindred, a mysterious and reclusive cult, reside.  While Scully interviews one of the young men of the sect, Mulder discovers a bizarre ritual held in a strange underground catacomb. 

No specific dates indicated. Dates given are speculative based on Winter season.

1/10/94 – 1/11/94


Season 1: Episode 16

1x15 Young at Heart

 Mulder is informed by his former partner, Reggie Purdue, that a criminal he put away years ago,  John Barnett, and who was supposed to have died in prison, has returned to taunt him as he commits a new spree of crimes.  Further investigation shows that the doctor who had pronounced Barnett dead had his license revoked for having experimented with reversing the aging process.

No specific dates indicated.  Dates given are speculative based on Football season and winter month.

 2/1/94 – 2/6/94


Comic: The X-Files #3-4 (Mar-April 09


Trade pb: The X-Files: Chapter 3 (Wildstorm)

The designated dates indicate 2009 or 2010 and must be ignored. Frank Spotnitz, who headed the project, indicates that these stories take place "during [Mulder and Scully's] prime years at the FBI."  Year is based on the nearest year when there existed a Tuesday the 8th in February.

2/8/94 – 2/10/94


Season 1: Episode 17

1x16 E.B.E.

Mulder and Scully discover evidence of a government cover-up when Deep Throat gives Mulder evidence that a UFO shot down in Iraq has been secretly transported to the US.  Seeking help,  Mulder introduces Scully to the Lone Gunmen -- an extreme government watchdog group.  Scully believes them paranoid until she discovers surveillance equipment in her pen.  Mulder discovers that Deep Throat has misled him and confronts him.  Deep Throat later tells him that when in the CIA, he was one of three men to carry out the act of exterminating an extraterrestrial biological entity, and that it has haunted him and inspired him to use Mulder as a means of atoning.  First appearance of The Lone Gunmen: Langly, Frohike and Byers.


Book: #9: E.B.E. (Harper, 1995)

Pitcher and Catcher Spring training begins in mid-Feb.  Introduction of The Lone Gunmen.

2/14/94 – 2/18/94


Short Story: "Back in El Paso My Life Will Be Worthless"

From the book: The X-Files: Trust No One (IDW)

(Coming soon)



Season 1: Episode 18

1x17 Miracle Man

Mulder and Scully investigate a young faith healer who's miraculous powers of healing appear to be turning to evil ends when those he tries to heal end up dead.


Book: X-Files #16: Miracle Man (Harper, 1997)

 Scully dates her autopsy (on the 2nd day) as 3/7.  Book contains a continuity error dating a headstone 1997.

3/6/94 – 3/8/94


Season 1: Episode 21

1x20 Tooms

 Mulder becomes personally involved when Eugene Tooms, the mutant serial killer he'd captured months earlier (in Episode 1x02: Squeeze) is released and is free again to extract and eat human livers.  After several foiled attempts to kill, however, Tooms sneaks into Mulder's apartment while he sleeps and mars his face with Mulder's shoe in order to frame him.  The ploy works and Assistant Director Skinner forbids Mulder to go near him.  First appearance of Walter Skinner.

Sequel to "Squeeze." Skinner's 1st appearance. No specific dates indicated. Dates given are speculative, but occurs "months" after July '93

3/14/94 – 3/17/94


Season 1: Episode 19

1x18 Shapes

Mulder and Scully travel to a Native American reservation to examine strange deaths which appear to be linked to beliefs in a Manitou, a werewolf legend haunting the region.


Book: X-Files #6: Shapes (Harper, 1995)

Book: The X-Files Collection (Voyager, 1997)

Dental reports (UA) indicate most recent exam on 3/19.

 3/21/94 – 3/23/94


Season 1: Episode 22

1x21 Born Again

A series of murders in linked to a little girl who may be the reincarnated spirit of a murdered policeman.

Date indicated on sign-in log. Events of "Tooms" referenced as having occurred relatively recently.

3/27/94 –  3/31/94

Epilogue: 4/19/94


Short Story: "The Beast of Little Hill"

From the book: The X-Files: Trust No One (IDW)

The date noted in the book is erroneous, as another episode takes place at that time.  I subtracted a year to arrive at this open time-frame.



Season 1: Episode 23

1x22 Roland

Mulder and Scully investigate the deaths of two rocket scientists apparently linked to Roland, a retarded janitor.  A background check, however, reveals that the janitor is twin to one of the deceased scientists who's remains have been cryogenically preserved.

Date obtained from computer screen.

4/24/94 – 4/29/94


Season 1: Episode 24

1x23 The Erlenmeyer Flask

Working on a tip from Deep Throat, Mulder and Scully discover that the government has been testing Alien DNA on humans with disastrous results.  Deep Throat is shot by Crew-Cut Man.  The X-Files are closed.

Deep Throat killed.  X-Files shut down on 5/25/94. 

5/8/94 – 5/12/94

Epilogue: 5/25/94 



Episode Theme Codes


A: Artificial Intelligence, technology and machines gone bad

B: Bugs, creepy-crawlers and parasitic pests

C: Cults, tribal practices and bizarre religious rites

D: Drama

E: Evil experiments and other scientific blunders

F: Fantasy, Philosophic theory, and Time paradoxes

G: Government conspiracies (unrelated to the mythology)

H: Humor

K: Killers (serial & spree), psychopaths; the human monster

L: Local legends: Bigfoot, lake monsters, etc.

M: Monsters, mutants and malformed menaces

N: Nightmares, Dreams and Visions

O: Occultism, devil worship, demons and dark forces.

P: Psychic manifestations (telepathy, telekinesis, etc.,)

R: Reincarnation, transmigration and other pagan beliefs

S: Spirits, ghosts and apparitions

U: UFO's and aliens (unrelated to the mythology)

V: Viruses, bacteria and other nasty microbial matter

W: Werewolves, vampires and zombies

X: The Alien/Conspiracy main plot thread of the mythology

?: Unknown