This article argues that the foundational separation between psychoanalysis and experimental psychology was challenged in important ways by psychoanalytic infant researchers. Through a close examination of American psychoanalyst René Spitz (1887–1974), it extends John Forrester’s conception of reasoning in cases outside classic psychoanalytic practices. Specifically, the article interrogates the foundations of reasoning in cases—the individual, language, and the doctor–patient relationship—to show how these are reimagined in relation to the structures of American developmental psychology. The article argues that the staunch separation of experimental psychology and psychoanalysis, reiterated by philosophers and historians of psychology, is flimsy at best—and, conversely, that the maintenance of these boundaries enabled the production of a cinematic case study. Spitz created films that used little language and took place outside the consulting room with institutionalized infants. Yet key aspects of the psychoanalytic case, as put forth by John Forrester, were depicted visually. These visual displays of transference, failure, and interpersonal emotions highlight the foundations of what Forrester means by reasoning in cases. The article concludes that Spitz failed at creating classic psychoanalytic evidence, but in so doing stretched the epistemology of the case.