How might we usefully conceptualize romantic love in historical work? Historians of the emotions typically move across and between disciplines in the humanities along with the social, behavioral and cognitive sciences in an effort to define and explain the emotions. Using romantic love as a case study, this article tests the effects of this interdisciplinary movement. It undertakes an experiment in interdisciplinary reading by closely examining key moments of definition and conceptualization of romantic love by psychologists, sociologists, anthropologists, neuroscientists, literary scholars, and historians in the last two decades. This interdisciplinary reading experiment demonstrates that, taken together, the scholarships of romantic love offer an uncertain and incoherent picture of the emotion’s characteristics and behaviors. This uncertainty poses some problems for the romantic love historian, frustrating attempts to firmly establish the ground from which to investigate the emotion. This article argues, however, that this uncertainty might also provide an opportunity, directing the romantic love historian towards the emotion’s one (remaining) essential component: the romantic couple.