The senior crew discuss their latest mission: to make contact with the Tamarian race who have been transmitting signals toward Federation space for weeks. The Enterprise makes contact with a Tamarian ship in orbit around the planet El-Adrel. Though the universal translator can translate their words, the Tamarians only communicate through metaphor which baffles the Enterprise crew. Likewise, the Tamarians cannot understand Picard's straightforward use of language. Frustrated by their failure at communication, the Tamarian captain, Dathon, has himself and Captain Picardtransported to the planet's surface. The Tamarians then create a scattering field in the planetary atmosphere to prevent transport functions from being used on either captain. On the surface, Dathon utters the metaphorical phrase "Darmok and Jalad at Tanagra" and tosses Picard a dagger. Picard mistakes this as a challenge to a duel and refuses. As night falls, Picard fails to make a fire and Captain Dathon shares his fire with the phrase "Temba, his arms wide". The next morning, Dathon comes running and then Picard realizes that there is also a hostile predator in the area that is stalking them both. Picard finally begins to understand the way the other race communicates when he recites one of the metaphors and sees the meaning underneath it. The two attempt to fight the beast together, but, because of the Enterprise's ultimately unsuccessful transporter attempt preventing Picard from participating in the battle, Dathon is mortally wounded.
On the Enterprise, First Officer Riker and the crew struggle to understand the alien's language and Riker has Commander Data work with ship's counselor Troi in hopes of translating it. Lt. Worf, in the meantime, thinks that the Captain is being tested as a warrior and advocates an aggressive stance which Riker says he will take as a last option. Riker has Worf take a shuttlecraft to try to retrieve the Captain which fails when the aliens disable the craft and force it to return to the Enterprise. Chief Engineer La Forge and Worf work on a way to disable the Tamarian's scattering field to beam up Picard, while Troi and Data work on deciphering the Tamarian language. They deduce that the Tamarian language is entirely based on metaphors from Tamarian folklore. They learn that Darmok was a hunter and Tanagra is an island, but nothing else. Without knowing the stories behind the metaphors, the Tamarian language remains indecipherable.
While tending to Dathon's wounds, Picard deduces that Darmok and Jalad were two warriors who met on an island called Tanagra and had to cooperate to defeat a dangerous beast dwelling there, becoming friends in the process. Dathon tried to recreate this event between him and Picard on El-Adrel, hoping that their shared adversity would forge a friendship where words had failed. Picard recounts for Dathon the Epic of Gilgamesh, a human story that parallels the allegory of Darmok and Jalad's. Dathon seems to understand the story, but eventually succumbs to his wounds.
The Enterprise fires on the Tamarian ship, disabling the scattering field, and beams up Picard. Picard uses his newfound knowledge of Tamarian metaphors to communicate with the Tamarians and end the battle; the Tamarians record the story as "Picard and Dathon at El-Adrel", adding a new phrase to their language. Picard mourns Dathon, who sacrificed his life to open relations between their two cultures.