It features an extended trip to and through Bellona, a fictional city in the American Midwest cut off from the rest of the world by an unknown catastrophe.

Inexplicable events punctuate the novel: One night the perpetual cloud cover parts to reveal two moons in the sky.

One day a red sun swollen to hundreds of times its normal size rises to terrify the populace, then retreats across the sky to set on the same horizon.

Gangs roam the nighttime streets, their members hidden within holographic projections of gigantic insects or mythological creatures.

The novel's protagonist is "the Kid" (sometimes "Kidd"), a drifter who has partial amnesia: he cannot remember either his own name or those of his parents, though he knows his mother was an American Indian.

Possibly he has schizophrenia: the novel's narrative is intermittently incoherent (particularly at its end), the protagonist has memories of a stay in a mental hospital, and his perception of reality and the passages of time sometimes differ from those of other characters.

In addition, he is dyslexic, confusing left and right and often taking wrong turns at street corners and getting lost in the city.

As he crosses the bridge in the early morning darkness, the young man meets a group of women leaving the city.

Once inside Bellona, an engineer, Tak Loufer, who was living a few miles outside of the city when the initial destruction happened, meets and befriends him.

In Chapter II, "The Ruins of Morning", Kid returns to the commune the next day and receives the notebook from Lanya Colson, one of the two women from the evening before.

We meet or learn about several other characters, including George Harrison, a local cult hero and rumoured rapist; Ernest Newboy, a famous poet visiting Bellona by invitation of Roger Calkins, publisher and editor of the local newspaper, The Bellona Times; Madame Brown, a psychotherapist; and, later in the novel, Captain Michael Kamp, an astronaut who, some years before, was in the crew of a successful Moon landing.

As the novel progresses, Kid falls in with the Scorpions, a loose-knit gang, three of whom have severely beaten him earlier in the book.

(Much of this suggests the American "mythical folk hero," Billy the Kid, whom Delany used in his earlier, Nebula Award-winning novel, The Einstein Intersection [1967].)

In Chapter VI, "Palimpsest", Calkins throws a party for Kid and his book, Brass Orchids, at his sprawling estate.

While Calkins himself is absent from the gathering, there are extended descriptions of the interactions between what is left of Bellona's high society and, in effect, a street gang.

Recalling Kid's entry into the city, the final section contains a near paragraph-for-paragraph echo of his initial confrontation with the women on the bridge.

This time, however, the group leaving is almost all male, and the person entering is a young woman who says almost exactly what Kid did himself at the beginning of his stay in Bellona.

"[4] Almost certainly this is also the case with Dhalgren: Writing about the novel both as himself and under his pseudonym K. Leslie Steiner, Delany has made similar statements and suggested that it is easy to make too much of the mythological resonances.

Delany conceived and executed Dhalgren as a literary multistable perception—the observer (reader) may choose to shift his perception back and forth.

This happens well before a point in the novel where Kid specifically states that he only wrote the poems, and "all that other stuff" was already in there when he received the notebook.

The repeated motif of a scratch down the lower leg of several female characters at different points in the novel is yet another example.

Delany has cited poets W. H. Auden, Rainer Maria Rilke, and Paul Valéry as influences on the book, as well as John Ashbery's poem "The Instruction Manual".

"[15] Darrell Schweitzer expressed the opinion, "Dhalgren is, I think, the most disappointing thing to happen to science fiction since Robert Heinlein made a complete fool of himself with I Will Fear No Evil.

"[19] Delany has speculated that "a good number of Dhalgren's more incensed readers, the ones bewildered or angered by the book, simply cannot read the proper distinction between sex and society and the nature and direction of the causal arrows between them, a vision of which lies just below the novel's surface.

[20] In 2017, a multimedia performance called Dhalgren Sunrise was staged by Fort Point Theatre Channel in Chelsea, Massachusetts.

[21] In 3 Body Problem (TV series) S1 E6, the man who will be following Ye Wenjie, is seen reading Dhalgren sitting at a table.

Dhalgren was officially published in January, 1975 (with copies available on bookshelves as early as the first week in December, 1974), as a paperback original (a Frederik Pohl selection) by Bantam Books.