[T]he writing itself is also about mixing things up, grafting flights of descriptive fancy with hunks of conversational dialogue, pausing briefly to sketch passing characters or explain a bit of a bygone world.—Lisa Schwarzbaum in Entertainment Weekly
Several reviewers considered Middlesex to be overly verbose. The Economist called the novel "ponderous" and that the main story (that of Cal) does not "get off the ground until halfway through" the book. Time 's Richard Lacayo concurred; he considered the hundreds of pages about Cal's grandparents and several historical events to be trite, making Middlesex 's focus "footloose" in some spots. Several passages in the novel exhibit Eugenides' obsession with "verbose voluptuousness". An example noted by Thea Hillman in her review is an incident in which Cal says, "I sat in my seat, in a state of voluptuous agitation, of agitated voluptuousness, until my stop. Then I staggered out." A contrary opinion on the verbosity is given by Daniel Soar in his article for London Review of Books. According to Soar, Eugenides did "both background and foreground in all the necessary detail", seamlessly shifting from past to present. Despite the implausible tone of the novel's events, the author successfully makes them "elaborately justified and motivated". The quality of Middlesex 's writing was uneven in the opinions of Hillman and another reviewer, Sebastian Smee. The latter pointed out that Eugenides occasionally moves from the heartfelt ("I remember the first time we took off our clothes in front of each other. It was like unwinding bandages") to the "trashily journalistic" ("You've heard of installation artists? Well, the Object [a heavy smoker] was an exhalation artist") on several occasions.
Humor and irony are frequently used in the book. Mark Lawson of The Guardian considered the narrator's tone to be "sardonic[ally] empath[etic]", and other critics have characterized the beginning of the novel as comical. When Cal is baptized as an infant by Father Mike, a Greek Orthodox clergyman, the priest receives a surprise: "From between my cherubic legs a stream of crystalline liquid shot into the air ... Propelled by a full bladder, it cleared the lip of the font ... [and] struck Father Mike right in the middle of the face." Derek Weiler of the Toronto Star noted that Eugenides has witty commentary about German compound words and the "horrific qualities of public men's rooms". The author employed another writing device—abrupt incongruity—in describing Desdemona's physical appearances to suggest that her incestuous acts should be taken lightly when judging her. In describing her hair, he wrote that her "braids were not delicate like a little girl's but heavy and womanly, possessing a natural power, like a beaver's tail". According to Penelope Music of Book Magazine, the mismatch in tone of the final two words compared with the rest of the sentence was such that the reading experience was changed from "run-of-the-mill magical realism to true, subversive comedy". An instance of irony is illustrated by Cal's grandparents and parents: His grandparents assimilate into American culture through hard work and struggles while retaining certain old customs. His parents, however, abandon their roots for a more comfortable lifestyle. In another incident, the diner owned by the Stephanides is engulfed in flames during the 1967 Detroit riot. Cal ironically notes that "[s]hameful as it is to say, the riots were the best thing that ever happened to us." The diner was insured and the Stephanides gain a windfall payout.
Middlesex is written in the form of a memoir, and switches between the first and the third person in several spots. Used as a comedic device, the third person narratives illustrate Cal's estrangement from Calliope: When he refers to her in the third person, he is identifying her as someone other than him. Patricia Chu, a scholar of English literature, noted the effectiveness of this style in the chapter where the adolescent Callie searches for information on hermaphroditism. As the teenager reads Webster's Dictionary, following the trail of definitions related to her condition, she reaches the entry for hermaphrodite. The narration switches from personal to external, lending poignancy to the character's final discovery as she is confronted by the word "monster".
Although the protagonist switches gender throughout the book, Cal's manners of speech and thought are identical to Callie's. Believing that males and females have no inherent disparities in their writing styles, Eugenides treated Cal and Callie as the same person, in terms of narrative voice. He also fixed the narrative voice in terms of age by setting up Cal to relate the entire story at one time. Eugenides gave his protagonist a mostly male outlook, justifying his treatment with the reasoning that Cal or Callie was a man in terms of appearance, sexual desires, and the brain. He asked his wife and other women to review his approaches on Cal's feminine views. The "emotional stuff" was accurate but Eugenides had to refine certain details, such as those about toenail polish.
At the beginning of the book when Cal discusses his family's history and actions prior to his birth, he speaks in an androgynous voice, with limited omniscience; he acknowledges that he is fabricating some of the details. John Mullan, University College London's professor of English and a contributor to The Guardian, wrote that by permitting Cal to be unrealistically aware of fellow characters' thoughts, Eugenides intentionally contravenes an elementary standard in storytelling fiction. In the novel's closing pages, Cal provides minute details about his father's dying moments and thoughts in a nonsensical car accident even though he is several thousand miles from the scene and only learns of the tragedy from his brother. Cal has the ability to dwell in the minds of others because as a female who has become a male, his identity is not confined by his own body. According to Mullan, this "mobility of identification becomes a narrative principle" and is thoroughly exploited in Middlesex. The novel follows the principle that people are molded by events prior to their birth, and Eugenides explores a character's prenatal life in terms of his or her genes; the narrator is, however, subject to the principle that whatever he does not know is of his imagination. As such, contradictory statements highlight the unreliable nature of Cal's narration. While narrating the story that pre-dates his birth, he remarks, "Of course, a narrator in my position (prefetal at the time) can't be entirely sure about any of this." However, he later says, "I alone, from the private box of my primordial egg, saw what was going on." Cal's dubious omniscience, doubtful narration, and parodies combine to show that his unreliability is an act of mischief.
Mullan remarked that Eugenides' narrator has a proclivity to reveal events that will happen in the future. Cal is a narrator who is absorbed in how his fate has been shaped. Cal eschews a chronological telling of the story, where he shares the characters' nescience. He chooses instead to relate the story beginning with his future knowledge. Cal's genes reflect an anticipation of the future: the disclosure of his actual sex identity. Cal mimics this "genetic inevitability" by enjoining the readers to know the future prior to its occurring. Mullan observed that "[f]or the reader, apprehension predominates over surprise" as a result of this narrative style.
The Kirkus Reviews described Middlesex as a "virtuosic combination of elegy, sociohistorical study, and picaresque adventure", and Adam Begley in The New York Observer called it "a hybrid form, epic crossed with history, romance, comedy, tragedy." Other reviews also categorized the book under various genres. Covering the lives of three generations of the Stephanides family, Middlesex is considered a family saga by novelist Geraldine Bedell. The book is more than a mere family saga, according to Samuel Cohen in his paper for Twentieth Century Literature; it depicts the Stephanides' trials and tribulations through historical events. Cohen is not convinced by Eugenides' declaration that Middlesex was not conceived as a historical novel; he said the novel satisfied much of the criterion for the genre. Cal, narrating his story in 2002, describes events from the early 1920s to the mid-1970s. According to Cohen, the difference in timeframes, at least 25 years apart, "establishes that the novel is set safely in the past".
According to Stewart O'Nan of The Atlantic, Cal's narration evokes the style of the picaresque novel, retelling events that have already occurred and foreshadowing the future through "portentous glimpses". Francisco Collado-Rodríguez, a professor of American Literature, classified the beginning of Middlesex as a historiographical and metafictional chronicle for its discussion of events such as the Greco-Turkish war and the Great Fire of Smyrna. He also considered the first section of the novel as a tragicomedy about the Stephanides' migration from Greece and assimilation into America. Soar posited Desdemona and Lefty's passage as a romantic comedy: the lovers, brother and sister, pretend to be strangers who meet for the first time, attempting "to unknow themselves, to remythologise themselves by developing a past they could live with, unfamiliar and therefore permissible". As the story progresses, Middlesex becomes a social novel about Detroit, discussing the seclusion of living in a 1970s suburb. At the end of the novel, the story adopts the tone of the detective genre.
The novel is characterized as a "dramatic" Bildungsroman with a "big twist" because the coming-of-age story is revealed to be the incorrect one: after being nurtured as a woman, Cal must instead learn to become a man. The book has "two distinct and occasionally warring halves". Whereas the first part is about hermaphrodites, the second is about Greeks. The latter half, "full of incest, violence, and terrible family secrets", was considered by Daniel Mendelsohn, an author and critic, to be more effective because Middlesex is largely about how Callie inherited the momentous gene that "ends up defining her indefinable life".
Writing for The New Republic, James Wood classified Middlesex as a story written in the vein of hysterical realism. He said the novel is influenced by its own recounting of "excitements, patternings, and implausibilities that lie on the soft side of magical realism". Such moments in the book include how two cousins conceive "on the same night and at the same moment" and how years later, those children marry each other. Woods also pointed out the seeming coincidences that involved locales. Smyrna is the burning city from which she flees to start a new life; New Smyrna Beach is where she spends her retirement. Effectively serving as a double entendre, the title of the book refers to the name of the street where Cal stays at and describes his situation: a hermaphrodite brought up as a girl but who decides to become a boy. Cal's condition is also reflected in his choice of locale to narrate the novel: Berlin is a city formerly of "two halves or sexes" (East and West).