"The Sword of Kahless" is the 81st episode of the American science fiction television series Star Trek: Deep Space Nine, the ninth of the fourth season.

The episode was directed by Star Trek: The Next Generation alumnus LeVar Burton, and featured the return of John Colicos as Kor.

Jadzia Dax (Terry Farrell) to help to find the ancient Sword of Kahless, the legendary founder of the Klingon Empire.

Due to time restraints in filming, there were edits made to the scripts and the production team were forced to make best use of the cave sets which had been seen on the show previously.

The sword itself was created specifically for the episode, and was made to seem more elaborate than the bat'leths previously seen in Star Trek, including hand etchings to make it appear similar to Damascus steel.

Although producers were disappointed with the initial fan reaction, critics later gave a mostly positive response to the episode and compared it to Indiana Jones and The Treasure of the Sierra Madre.

Kor (John Colicos), a revered Klingon warrior, is in Quark's bar telling stories of past battles to his friend Lieutenant Commander Jadzia Dax (Terry Farrell).

They are attacked by Toral (Rick Pasqualone), son of Duras, who hired the Lethean and wants the Sword for the prestige of finding it.

As they travel through the caves, the Klingons are affected by the prestige of the Sword: Kor begins to talk about how it would allow him to overthrow Chancellor Gowron and Emperor Kahless II; but Worf believes that he should be the one to lead their people.

Dax helps Worf save Kor, and afterwards takes possession of the Sword because she thinks the two Klingons cannot be trusted with it.

Hans Beimler, who converted Danus' story into a teleplay, was aware of the mythology of the Grail as he wrote the script and wanted to avoid giving the sword any mystical or magical powers.

In The Original Series first-season episode "Errand of Mercy", Colicos had portrayed Star Trek's first main character Klingon.

Originally, the character, played by JD Cullum, was introduced in the TNG two-part episode "Redemption", when he sought the leadership of the Klingon High Council alongside his aunts Lursa and B'Etor.

[6] He used religious tones to accompany appearances of the sword itself, specifically when it is first found by Worf, and said, "If the audience isn't made to understand the spiritual importance of that weapon, then we have no episode".

[17] It was decided that the sword needed to be different from other bat'leths seen on the show,[6] and so a new hardened aluminium prop was ordered after numerous designs by John Eaves were considered on paper.

[7] "The Sword of Kahless" also featured new prop designs for Starfleet-issued over-the-shoulder bags and the camping equipment used in the cave sequences.

[20] Jamahl Epsicokhan of Jammer's Reviews compared the episode to an Indiana Jones story and said that it was a "enjoyable fable for a simpler time".

He praised the musical score by David Bell and thought that the episode was the perfect vehicle for Worf, saying that Michael Dorn gave a strong performance.