What can we hope to learn about a person from a split-second portrait? The expression that confronts the viewer’s gaze—startled, friendly, or shy—undoubtedly affects how we feel about the person. But what if we are faced with dozens of photographs of the same person? Or several sets of seemingly identical photographs taken a fraction of a second apart and reflecting almost imperceptible change? New York–based artist Roni Horn has long been fascinated with the concept of personal identity and how it is—or is not—represented by the photographic portrait. This book brings together Horn’s most recent work, a site-specific series designed for the Schirn Kunsthalle in Frankfurt. Continuing in the tradition of her earlier work, the series makes use of multiple images of the same subjects in order to explore similarities and differences in portraits, including a set featuring Isabelle Huppert, in which the iconic French actress portrays characters past. Horn is one of the most intriguing American contemporary artists and the subject of major recent retrospectives at the Whitney Museum of Modern Art and the Tate, and this book offers readers a look at her most recent work.