Irene, the main character of Passing, values security above all else. She seeks to control those around her in order to maintain a stable life that she believes will give her a sense of safety and permanence. Irene has total confidence that her decisions are best for her husband Brian and their boys, regardless of what they think. This drive to avoid uncertainty affects her response to anything she disagrees with, from Brian’s talking to the boys about sex and racism to his desire to move to Brazil. She pushes him to continue a career in medicine, work he hates, because that career gives her financial and social stability. However, for all her work to control the conditions of her life, she does not ever feel fully secure. Her desire for safety is the basis for the conflict that drives the plot.

Clare’s arrival in Irene’s life upsets all the structures Irene has built to give herself a sense of safety. Clare is Irene’s foil, as comfortable with danger as Irene is terrified of it. Where Irene seeks safety, Clare seeks freedom. Though Clare is Black, she lives her life as a white woman married to a deeply racist white man. Nevertheless, after rediscovering Irene, Clare begins socializing more and more in Harlem and with Black people. She comes to Irene’s house uninvited and pushes her way into Irene’s social world while refusing to accept its limits. Clare gets Brian to invite her to Irene’s tea party, spends time talking with the Black maids, and insists on attending the Negro Welfare League dance. Irene claims she is attempting to keep Clare at a distance for her own sake, citing the danger of Bellew’s discovering her true race, but increasingly Irene’s true objection is Clare’s refusal to be controlled by Irene. When Irene realizes Clare and Brian are having an affair, the last of the loyalty to race and friendship Irene has felt towards Clare gives way to her own self-interest, and she puts her need for safety above all else. 

The moment of the novel’s climax, when Irene chooses the stability of married life over Clare’s safety, is put in motion by her decision to pass for white when she first meets Bellew, rather than to face the unpleasantness that would result if she had spoken up against his racist comments. Bellew’s belief that she is white sets up the inevitable conflict that arrives when he sees her with Felise. As Larsen points out early in the novel, people like Bellew do not see the Blackness of people who look like Irene and Clare unless they see them with other unmistakably Black people. Seeing Irene with Felise breaks the illusion of her whiteness for Bellew, which in turn causes him to realize that Clare is also Black. Irene understands in that moment, first unconsciously and then clearly, that if Bellew ends his marriage to Clare, Irene’s marriage to Brian will be at risk. Irene cannot accept that disruption to her settled life.

Irene’s decision not to warn Clare about her second meeting with Bellew and its likely consequences is driven by her desire for security. She can live with Brian and Clare’s affair, but she will not risk the potential dissolution of her marriage that would result if Bellew were to divorce Clare. While the book leaves the question of whether Clare fell to her death or was pushed unanswered, Irene’s one thought as she rushes towards Clare is that she cannot allow her to be free. In the moment before Clare falls, the catalyst for Irene’s anger is Clare’s smile. For Irene, Clare’s refusal to live by the same careful rules she follows represents an assault on Irene’s sense of what is right. Clare is the one person in Irene’s life she cannot control. More than the affair, it is Clare’s willingness to embrace freedom over safety that enrages Irene.
Although the book’s title seems to refer to Clare’s life, it applies to Irene’s role in the story as well. Irene prides herself on living as Black despite being light enough to pass, finding Clare’s choice to live as white both dangerous and repugnant to her sense of loyalty to race. Irene remarks to Felise that she only passes for convenience, a distinction she believes matters, but Larsen’s choice to have her say those words to Felise, who cannot pass, suggests that this is a false distinction. Irene passes for the sake of claiming luxuries she would otherwise be barred from, like theater tickets or the cool comfort of the white-only Drayton Hotel on a hot day. Clare, on the other hand, did not begin life with Irene’s wealth and social privilege. Clare’s passing, in that sense, is a more necessary and pragmatic decision. Early on, it is her best chance of escaping a life of poverty with her racist white aunts. Likewise, Clare’s death seems to be the outcome of the risks she has chosen. However, it is Irene’s need for security that leads to Clare’s death, both in the sense that Irene fails to warn Clare that Bellew likely knows she is Black and that Irene runs toward Clare, precipitating her fall, because of her fear of how Clare’s freedom will threaten her stable life. Throughout the book, Larsen places Irene’s need for safety in conflict with Clare’s comfort with danger.