Rather than use the "virginity-sexual tango" trope of most historical romance novels,[4] Koen sought to circumvent the "rules" of the genre and concentrate on characterization.

Koen engaged in an intensive research period in the eighteenth century using approximately 300 books, which she often obtained from a local university's library.

Naggar mailed the manuscript to five major publishing companies,[2][3] with Random House purchasing it for a "whopping" $350,000 in August 1985, which was at the time a record for a new novelist.

While learning to navigate through Parisian society, Barbara remains in love with her husband but Roger has no thoughts at all for his young bride other than mere fondness.

The plot jumps forward to 1720 England, where the country is unknowingly approaching the South Sea Bubble economic collapse; Barbara has separated from her husband and conducted affairs with several men in Paris and London.

Still in love with Roger despite his affair, she is unhappy and becomes horrified when she discovers that one of her jealous lovers, Lord Charles Russel, killed Jemmy, a young nobleman who she accidentally slept with for one night.

Barbara's only surviving sibling, Harry, is in severe debt and commits suicide; many citizens blame Lord Devane, who helped run the South Sea Company, for the country's finances.

Stricken and in mourning, Barbara holds a public memorial in London for her deceased husband, despite being warned that it would draw attention to his estate during the Parliamentary inquest into the financial crisis.

[3] Before she began writing it, Koen envisioned creating a story about the relationship between a young woman and an older man, a plot element riddled with emotional tension that required much planning and foresight.

"[4] Media stories angled the book's backstory as a "phenomenon," particularly because it was purchased by a prestigious publisher at such a high price for a first time novelist.

"[3] After reviewing the hype surrounding the book, author Barbara Schaaf concluded that its prose "was first-rate – literate and with flashes of timeless insight.

"[9] Schaaf added that Koen has a "fine eye for art, architecture, fashion, manners and relays the everything," though she critiqued the author for sometimes inserting too many historical details.

[9] She believed that the book especially shone in depicting the South Sea Bubble; "most historical writers," Schaaf opined, "neglect the economic background of their periods, regardless of its importance, and [Koen's] grasp of a complicated situation makes it as fascinating as her descriptions of the sexual behavior of the upper and lower classes.

"[9] People's Harriet Shapiro declared that Through a Glass Darkly "is no run-of-the-mill bodice buster, trade slang for bosom-heaving historical romances.

Koen paints a lavish, carefully researched portrait of a young woman's turbulent coming of age in 18th-century England and France.

"[3] Texas Monthly asserted that characterization was Koen's greatest asset, though the story's "sense of pacing falters" after two hundred pages.

[5] In a guest column for The New York Times, author Erica Jong called Koen's work a "well-researched, workmanlike historical novel [...] of the sort that Kathleen Winsor or Thomas B. Costain used to write: packed with details of costume, architecture and cuisine, populated by rudimentary paper-doll characters, full of undigested Continued on next page gobbets of research.

"[12] Jong shone a negative light on some of the characters, which she believed "seem[ed] derived from movies, mini-series and other books" and overshadowed by the attention to historical detail.