In this thoughtful treatise spurred by the 2015 death of African-American academic Sandra Bland in jail after a traffic stop, Gladwell aims to figure out the strategies people use to assess strangers--to "analyze, critique them, figure out where they came from, figure out how to fix them," in other words: to understand how to balance trust and safety. He uses a variety of examples from history and recent headlines to illustrate that people size up the motivations, emotions and trustworthiness of those they don't know both wrongly and with misplaced confidence. He relates, for example, the story of a whole cadre of American spies in Cuba who were carefully handpicked by American intelligence operatives, all of whom turned out to be pro-Castro double agents.

Gladwell writes in his signature colourful, fluid, and accessible prose, though he occasionally fails to make fully clear the connection between a seemingly tangential topic such as suicide risk and the book's main questions. In addition to providing an analysis of human mental habits and interactions, Gladwell pleas for more thoughtful ways of behaving and advocates for people to embrace trust, rather than defaulting to distrust, and not to "blame the stranger." Readers will find this both fascinating and topical.