G.H., an affluent amateur sculptor living alone in a penthouse apartment in Rio de Janeiro, attempts to recount a shattering experience that took place the day before. She addresses an imagined listener, inventing the presence of someone holding her hand, because she cannot face the memory alone. What happened has destroyed her sense of self. She compares her former identity to a "third leg" that kept her stable but prevented real movement; now that it is gone, the freedom terrifies her. She resolves not merely to retell but to "create" what happened, since giving form to the formless risks falsifying it, yet without form, nothing can exist for her.
Before describing the event, G.H. establishes who she was. She lived well, surrounded by an elegant apartment that reflected her talent for arrangement and imitation rather than authentic selfhood. Her identity was constructed entirely from how others saw her: The initials "G.H." stamped on her suitcases sufficed as a self. Her sculpture gave her a tone of permanent anticipation, a "pre-climax" that never needed fulfillment. She preferred the promise of living to living itself and existed, she now realizes, "in quotation marks."
On the morning of the event, G.H. lingers at the breakfast table, savoring the prospect of a quiet day arranging her apartment. Her maid, Janair, quit the day before, and G.H. decides to begin cleaning from the back, starting with the maid's room. She crosses the kitchen, pauses in the hallway to smoke, and looks down from the 13th floor into the building's courtyard, observing its industrial innards with a detached gaze. She heads into the dark hallway.
When she opens the door, she expects cluttered darkness. Instead she finds a stark, bright, nearly empty space flooded with harsh sunlight. Janair has stripped the room bare and claimed it as her own. On the whitewashed wall, G.H. discovers a charcoal mural: nearly life-sized outlines of a naked man, a naked woman, and a dog, drawn with coarse, rigid lines, staring ahead like mummies. G.H. recognizes the drawing as not decoration but a kind of writing. She suddenly perceives that Janair, a Black woman whose face G.H. had barely registered during six months of employment, may have regarded her with silent hatred, or at least a total absence of mercy. Trying to recall Janair's features, G.H. recognizes them as those of "a queen" and is disturbed to realize she had treated Janair as invisible.
The room strikes G.H. as the opposite of everything she has built. She resolves to reclaim it, but as she steps inside, she feels something collapsing beneath her constructed self. Trapped in the narrow space between the wardrobe and the bed, she cracks open the wardrobe door and comes face-to-face with a large cockroach. Her scream stays trapped in her chest. She reflects on her lifelong horror of cockroaches, creatures unchanged for 350 million years. The roach's presence transforms the room into something alive. G.H. tries to flee but trips, feeling not imprisoned but existentially pinned in place.
As the cockroach begins to emerge, G.H. feels a rapacious courage awaken in her. She slams the wardrobe door on the half-emerged body. The act feels enormous, as though she has broken through a dry surface to reach something beneath. But the cockroach is not dead. Half its body protrudes from the wardrobe, erect and still alive, looking at her.
She raises her hand to strike again but freezes when she sees the roach's face: its brown mouth, dry whiskers, black faceted eyes, ancient as a fossilized fish. She sits on the bed, unable to look away, feeling that in looking at the roach she is discovering her own deepest life, a crude, prehuman existence predating everything she has called herself. A thick, white matter begins oozing from the cockroach's crushed midsection. G.H. watches with mingled nausea and seduction, drawn into what she calls "the nothing," a living nothingness.
A progressive dissolution follows. G.H. feels she is exiting her personal world and entering a raw reality where neither compassion nor hope exists. She shrinks inward until she merges with Janair's drawn figure of the naked woman, recognizing that outline as what she has always been beneath her human constructions. She confronts the realization that "the world is not human, and that we are not human" (65). She connects the cockroach to the Bible's lists of unclean animals, reasoning that the unclean is forbidden because it represents the undisguised root of creation. A vague joy overtakes her, a joy without redemption. She recalls her pregnancy and subsequent abortion, connecting the neutral quality of that experience to the cockroach's gaze, and identifies the neutral as her deepest fear: the silence with which life makes itself.
She gives in. The present moment becomes absolute, hopeless and without future. She falls asleep briefly, then wakes and goes to the window, where Rio's rooftops transform into a vast desert landscape. She imagines herself surveying an ancient empire, planning an excavation to reach buried moistness beneath the surface, then turns back, acknowledging this vision as a legitimate enlargement of perception rather than madness.
Returning her gaze to the cockroach, G.H. enters what she identifies as hell: a demonic, orgiastic joy in the neutral substance of existence, a "Sabbath orgy" of things enjoying themselves at the level of raw matter. Then a sob rises, and the experience shifts. She realizes that what she called joy was actually her deepest suffering. She invokes God, feeling the sob transform terrible pleasure into lightness. She arrives at "neutral love," an inexpressive, continual joy like the noise of leaves in the wind. She declares that the state of grace exists permanently, that hope as she had practiced it was merely postponement of the present.
G.H. then confronts the climactic act. She recognizes that as long as she is disgusted by the roach, the world will elude her. True redemption requires eating the white paste oozing from the cockroach's body. She rises but vomits before completing the act. Calmed by the vomiting, she steps forward again, then loses consciousness. When she comes to, she realizes she has tasted the roach's paste, though she cannot consciously remember doing it. She spits furiously, then stops when she realizes she is undoing everything she achieved.
In the aftermath, G.H. arrives at final recognitions. She concludes that she did not need to eat the roach's paste as a heroic maximum act; the law of life is that each creature lives according to its own kind, and her task is to live fully within her own human existence. She articulates "depersonalization" as the stripping away of useless individuality until one becomes "the woman of all women," an objectification that paradoxically enables the deepest recognition of others. She describes "deheroization" as the true secret labor of a life: climbing high enough to fall, building a voice to arrive at muteness. She gives up, and in giving up, feels the world fit inside her weak hand. She experiences a quiet joy she names "trust," recognizing that she will never be equal to life, but that her life is equal to life. The novel closes with G.H. feeling "baptized by the world," having performed not the maximum act but the tiniest act, handing herself over to what she does not know.