Star Trek: Strange New Worlds season 2 episode 8, “Under the Cloak of War,” reveals the role that Doctor M’Benga (Babs Olusanmokun) played at the Battle of J’Gal. This dark and complex episode explored a corner of the Star Trek universe to which the Franchise rarely boldly goes. However, it is far from the first time that Star Trek has examined how war has affected (and continues to affect) humanity.

For this week’s edition of Trek Tuesday, here are 8 Star Trek episodes about war. Please note that this is not an exhaustive accounting of Trek‘s war episodes. Be sure and let us know your favorite!

“Errand of Mercy”

A Klingon, Commander Kor (John Colicos), and Captain Kirk (William Shatner) in the TOS episode "Errand of Mercy."

In the Star Trek: The Original Series season 1 episode “Errand of Mercy,” Captain James T. Kirk (William Shatner) and Mr. Spock (Leonard Nimoy) visit a planet populated by the Organians. There, they attempt to persuade the Organians into taking up arms against the Klingons, led by Commander Kor (John Colicos). Ultimately, the Organians are revealed to be an extremely advanced race. They subsequently force a cessation in the conflict between the Federation and the Klingons. Furthermore, the Organians accurately predict that Klingons and humans will one day cooperate with one another.

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“Errand of Mercy” is notable for being the first appearance of the Klingons. This seminal alien race will go on to play an important role in the Franchise. This includes the way Klingons are depicted in “Under the Cloak of War.”

“A Private Little War”

Captain Kirk (William Shatner) helps train several hill people in TOS season 2's "A Private Little War."

Total Ken energy (or “Kenergy”).

The TOS season 2 episode “A Private Little War,” Kirk visits and planet where Klingons have supplied firearms to one faction of locals. In order to balance the scales, Kirk leaves one hundred firearms for the other faction. Or as Kirk puts it, “A hundred… serpents for the Garden of Eden.”

As hinted by the title of the Star Trek: Lower Decks episode “Mugato, Gumato,” which pays homage to “A Private Little War,” the TOS episode was the debut of another important Trek alien, the Mugato. However, the deadly weapon left behind by the USS Cerritos is capitalism.

“The Savage Curtain”

"Team evil" represented by Genghis Khan (Nathan Jung), Kahless (Robert Herron), Zora (Carol Daniels DeMent), and Colonel Philip Green (Phillip Pine). Rock alien Yarnek (Bart LaRue; Janos Prohaska) has organized the team.

“Team evil”!

In TOS season 3’s “The Savage Curtain,” some of the Federation’s greatest historical military minds are gathered to face off against one another in a battle to the death. 

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According to Yarnek (Bart LaRue; Janos Prohaska), this fight is to determine whether the philosophy of “good” or “evil” is superior. The “good” side is represented by Kirk, Spock, President Abraham Lincoln (Lee Bergere), and Surak (Barry Atwater). Meanwhile, “evil” is represented by Genghis Khan (Nathan Jung), Kahless (Robert Herron), Zora (Carol Daniels DeMent), and Colonel Philip Green (Phillip Pine), a figure from Earth’s third world war. 

“Blood Oath”

Three elderly Klingon warriors: Commander Kor (John Calicos), Koloth (William Campbell), and Kang (Michael Ansara), reunited for DS9's "Blood Oath."

We Three Klingons.

When you ask a Trekkie to think of episodes related to war, several examples from Star Trek: Deep Space Nine are sure to spring to mind. In “Blood Oath,” several actors who had previously played Klingons returned to reprise their respective roles. This includes Colicos, who portrayed K0r in “Errand of Mercy.” Also present are Koloth (William Campbell), who originated in the TOS episode “The Trouble with Tribbles,” and Kang (Michael Ansara), who originated in the TOS episode “Day of the Dove.”

In this episode, three Klingon warriors reunite with Kang’s child’s godfather, the Dax symbiote (Terry Farrell), on DS9. The quartette has joined in a blood oath, swearing revenge on the criminal who murdered the three Klingon’s children. Just like “Under the Cloak of War,” this episode examines the lasting consequences of violence.

“In the Pale Moonlight”

Benjamin Sisko (Avery Brooks) sits in his quarters and addresses the camera in DS9's "In the Pale Moonlight."

Have you ever danced with the Garak…?

“In the Pale Moonlight” from Deep Space Nine season 6 isn’t just one of the best DS9 episodes about war. It’s widely considered to be one of the best DS9 episodes period. The memorable story is characterized by an ongoing conceit in which Captain Benjamin Sisko (Avery Brooks) directly addresses the camera while explaining why he made a morally questionable (but ultimately not regrettable) command decision. 

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If the episode title seems familiar to you, there’s a reason for that. It alludes to a line from Batman (1989). The full line is an inquiry by the Joker (Jack Nicholson) directed at multiple characters, including the eponymous hero (Michael Keaton): “Did you ever dance with the devil in the pale moonlight?”

“Once More Unto the Breach”

Commander Kor (John Calicos) on the bridge of a Klingon bird of prey.

Klingon on the Bridge!

The DS9 season 7 episode “Once More Unto the Breach” gives Kor one last moment of glorious battle before he goes not-so-gently into that good night. In this episode, the elderly Kor attempts to shuffle off his mortal coil via an honorable death before his mind is engulfed by the fog of age.

This desire is complicated by his relationship with Martok (J.G. Hertzler), who bears an extremely longstanding grudge against Kor. However, Kor ultimately achieves his goal of an honorable death during a desperate but successful attack against the Jem’Hedar.

“Chosen Realm”

Captain Jonathan Archer (Scott Bakula) and Pri'Nam D'Jamat (Conor O'Farrell) take in the consequences of a holy war in the ENT episode "Chosen Realm."

Behold, the wraith of faith!Star

In Star Trek: Enterprise season 3’s “Chosen Realm,” the NX-01 Enterprise is hijacked by Pri’Nam D’Jamat (Conor O’Farrell) and his followers. These religious extremists have been embroiled in a holy war based on a difference in beliefs.

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Eventually, it is revealed that the “difference in beliefs” in question is over whether their mythological creation of the universe lasted nine days or ten. At the end of the episode, D’Jamat believes his actions were justified. To convince him otherwise, Captain Jonathan Archer (Scott Bakula) beams down to his planet with him and shows him the devastation war has wrought.

“Battle at the Binary Stars”

"Battle at the Binary Stars" -- Ep #102 -- Coverage of the CBS All Access series STAR TREK: DISCOVERY. Pictured (l-r): Michelle Yeoh as Captain Philippa Georgiou; Chris Obi as T'Kuvma.  Georgiou stands with a weapon in her hand.

Photo Cr: Jan Thijs © 2017 CBS Interactive. All Rights Reserved.

On Star Trek: Discovery, a conflict between Klingons and the Federation ignites early on in season 1. “Battle at the Binary Stars” demonstrates the cost of war, demonstrated by the death of Captain Philippa Georgiou (Michelle Yeoh).

Getting better acquainted with Mirror Georgiou over the following two seasons has only served to underscore how terrible the loss of Georgiou Prime truly was. However, the heroic Starfleet Captain may be gone, but she is not forgotten. In the novel Star Trek: Strange New Worlds: The High Country by John Jackson Miller, Captain Christopher Pike is inspired to action by Georgiou Prime’s actions in Discovery‘s series premiere, “The Vulcan Hello.”

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