Fiction (1983), a collection of critical essays by female scholars such as Susan Gubar, Elizabeth Ermarth, and Nancy K. Miller that attempts to reexamine how women have been portrayed in literary texts. Writing a Woman's Life offers an examination of women's biographies and autobiographies, discussing a diverse range of works on notable women including George Eliot, Elizabeth Barrett Browning, Gertrude Stein, and Margaret Thatcher. In 1995 Heilbrun collaborated with Gloria Steinem to write the authorized biography The Education of a Woman: The Life of Gloria Steinem, combining a history of contemporary feminism with the life story of the high-profile feminist activist. The essays in The Last Gift of Time: Life beyond Sixty (1997) reflect on a desire that originated during Heilbrun's adolescence to commit suicide at the age of seventy, offering a candid and emotional look at the negative and positive aspects of the aging process. Heilbrun's When Men Were the Only Models We Had (2002) reflects on her admiration of such male critics as Clifton Fadiman, Lionel Trilling, and Jacques Barzun, while lamenting the rampant sexism she experienced in academia.

Writing under the name Amanda Cross, Heilbrun has published a series of mystery novels focusing on Professor Kate Fansler, an amateur sleuth and academic who teaches Victorian literature at a large uptown university. Fansler is portrayed as an independent and thoroughly modern heroine, with many of her adventures set against the backdrop of the intensely political world of university academia. In the Last Analysis revolves around Fansler helping a psychiatrist friend to clear himself of a murder charge after a patient is found dead in his office. The situation allows Fansler to deliver her strong opinions by way of witty literary allusions—her ability to quote appositely on every occasion becomes a hallmark of her style—while imaginatively reconstructing the murder scene. In The James Joyce Murder (1967) Fansler returns from doing research in the country to assist her young nephew who is accused of killing a neighbor. As Heilbrun further developed her feminist critical theory in works such as Reinventing Womanhood, several of the Amanda Cross mysteries began to take on a more political and socially conscious tone, particularly by focusing on the institutional sexism found in many American universities. A female graduate student is murdered in The Question of Max (1976) after she threatens her college's male literary-critical hegemony. In Death in a Tenured Position (1981) Fansler investigates the death of the first woman tenured in the women's studies program at Harvard University, with suspicion falling on the victim's faculty colleagues. An Imperfect Spy (1995) opens with the suspicious death of a woman faculty member at a conservative law school. In 1998 Heilbrun published The Puzzled Heart, in which Fansler's husband Reed is kidnapped by a group opposed to her feminist stance. The ensuing investigation forces Fansler into an extended examination of her personal and professional relationships. Fansler acts as an advisor to a new amateur detective, Estelle “Woody” Woodhaven, in Honest Doubt (2000). Both women investigate the murder of Charles Haycock, a disliked Alfred Tennyson scholar at a small New Jersey college. Throughout the novel, Fansler guides the exasperated Woody through the labyrinth of academic politics. Heilbrun has also published a collection of short stories, The Collected Stories of Amanda Cross (1997), which presents nine short mysteries most of which feature Kate Fansler as the protagonist.

Critical Reception

For her works of critical theory, Heilbrun has been consistently lauded for her ability to take complex feminist concepts and translate them into accessible language. Reviewers have praised her emphasis on women's writing and the role of women in literature, describing her analysis as erudite, engaging, and insightful. Though some scholars have derided Heilbrun's unswerving feminist perspective, others have applauded her use of fictional and autobiographical examples to expound on her central arguments. Heilbrun's Amanda Cross mysteries have attracted considerable attention for their complex plotting and positive female role models, despite some critical debate about detective fiction's sustainability as a genre for feminists. Additionally, many critics have complimented Death in a Tenured Position and An Imperfect Spy for raising important questions about the treatment of women by academic and literary institutions. However, some reviewers have questioned the validity of Heilbrun's biography of Gloria Steinem, The Education of a Woman, arguing that her collaboration and friendship with the feminist activist caused Heilbrun to focus on the more positive aspects of Steinem's life and career.