This paper argues that political scientists in Britain have, for the most part, failed to adequately understand Corbynism (i.e. the movement surrounding Labour Party leader Jeremy Corbyn) as a distinctive iteration of left politics. To substantiate this claim, we begin by mapping a consensus in British politics scholarship about the central features of Corbynism, namely that it is a misguided politics characterised by poor leadership, a "hard left" ideological orientation, and a populist flavour. In the second part of the paper, we suggest that this unfavourable characterisation of Corbynism relies on problematic analytic assumptions about leadership, the left, and populism. Furthermore, we argue that such narratives do not withstand empirical scrutiny, largely because they fail to do justice to the heterogeneous strands that constitute the politics of Corbynism. In the final part of the paper, we offer an explanation for political scientists' trouble with Corbyn, highlighting the continued dominance of the Westminster Model, widespread confusion surrounding the descriptive/normative relation, and considerable convergence between academic and media depictions of Corbynism. Overall, we suggest that political scientists' failure to take seriously the full complexity of the Corbyn movement requires rectification.