An alien race called the Tamarians meets the Enterprise in orbit of a planet to establish first diplomatic relations, where initial communications prove frustrating and bizarre because of the Tamarians' incomprehensible language, which when translated results only in phrases like "Darmok and Jalad at Tanagra." The Tamarian captain, Dathon (Paul Winfield), kidnaps Picard to the planet surface where the two attempt to come to some sort of understanding while a strange creature lurks on the other side of the rocks.
It's fascinating, how these Tamarian words, initially so nonsensical, ultimately end up taking on so much meaning. "Darmok" might be the ultimate Joe Menosky episode — one deeply rooted in ancient legends and strange cultures, and a story that's far more conceptual than your average storytelling fare. Essentially, you have a story that's being told through snippets of other stories that the characters are telling each other. In this vein of unique Menosky-scripted myths within myths, see also TNG's "Masks" (which I'll deal with down the road), DS9's "Dramatis Personae," and Voyager's "Muse." Granted, the level of success varied greatly among these episodes, but there's a kindred thematic current running through them all.
All of which means that it kind of pains me to say that I like, but do not love, "Darmok." I admire it more than I enjoy it, because to a certain degree this episode keeps itself at arm's length with all of its legends and metaphors and its striving to reach this conceptually ambitious place. The Tamarians, you see, have a language based completely on metaphors and storytelling, so in order to know what "Darmok, his arms wide" actually means, you need to know who and what Darmok himself represents.
That's a fascinating concept, but not one that's easy to convey on screen — or without a certain level of (granted, perfectly TNG-appropriate) exposition. The story frequently cuts back to the Enterprise, where sometimes too much is made of dealing with the procedural details of Riker trying to get past the Tamarians' energy field in the attempts to rescue Picard. And at times the story stalls dramatically; for stretches it's just two guys sitting on a rock trying patiently to break through the wall of confusion that stands between them. But in this conviction is also the story's strength. What I really like about "Darmok" is Picard's willingness to listen — really listen — and try to figure out what all of this means. (I think it takes a little too long for Picard to initially realize that this encounter is in fact not a death match, but once he gets over that misconception, the story demonstrates Picard's gifts for digging in for the long haul and fighting for diplomacy.)
Ultimately, Picard reaches that epiphany. The entire meeting was set up by Dathon in order to reenact an ancient Tamarian tale in which Darmok and Jalad fought together in much the same way Picard and Dathon do here. That's a neat narrative trick, but not one that completely makes me a die-hard advocate of this episode. Sometimes the experience of watching "Darmok" is as slow going as the process of Picard learning about it. But when you finally get to the end, you see how that patience pays off.