In this poem, the speaker observes the rows of fish that are put on display at a market. He describes the mackerel as luminous, seeming to glow with rainbow light, and striped with black bands that he compares to the leaden seams of Tiffany Studios' stained glass decor. The comparison is rather surprising and jarring; Doty draws an uncommon connection between the display of mackerel and the delicate, revered creations of a prestigious glass studio.

The speaker also likens the iridescence of the mackerel's scales to the sheen that appears in the sunlight shining on a soap bubble or on a slick puddle of gasoline. He states that there is also beauty—"splendor"—in their perfect sameness; there is nothing to distinguish one fish from another. This sameness indicates for the speaker the seeming expression of "one soul"—perfect copies of a divine template, endlessly repeated. The speaker then compares this glorious sameness to the craft of a jeweler who produces intricate and innumerable pieces that are made no less beautiful by their recurring reproduction.

At this point, the speaker turns his focus from the contemplation of the fish in order to attend to the listener. The speakers asks how the reader—how human beings—could iridesce like the fish do in their glorious sameness: "flashing participants, multitudinous" who live in a shimmering universe. He asks the reader if it is preferable to be an inimitable individual only to be lost, inevitably, in death because of this singularity. If an un-copied version of something is lost, it is gone forever. Thus, the soul of the separated individual is mortal in a way that the shimmering mass of fish are not.

The speaker claims that the fish prefer to be one of many participants in an unceasing replication of beauty rather than developing a singular, limited beauty. Even dead and lined up in a row, the speaker states that they still seem to be moving; their dead state is very similar to their live state, as though the fish care as little for their deaths as they did for their lives—though they seem happy nonetheless. The speaker states that their multitudinous, "selfless" states in both life and death "is the price of gleaming"—or the trade that is made for their brilliant iridescence.