This paper explores the power of images vis-à-vis the practice and theory of international law, with a focus on rules of customary international law, i. e. the unwritten general rules of international law, that apply to all states (as well as to non-state actors falling within their scope of application), irrespective of specific acceptance. As Sherwin writes: “We are awash in images.” States, international organizations (IOs), non-governmental organizations (NGOs), insurgents, terrorists and other groups of individuals of all sort, are in the news and our movies, on our TV screens, newspapers, internet and social media. Modern technologies, visual digital technologies, in particular, have a profound impact on the means and speed of communications across the globe and immensely facilitate the task of seeking information of all sort. In international law, images are a means for spreading knowledge about the practice of states and other actors. As with law in general, images are also found to be a valuable resource in explicating the rules of international law. They aid and clarify the analysis of international law and the determination of the existence and content of rules of customary international law. In contemporary international settings, however, modern technologies of visual representation are also a means for influencing the development of international law, i. e. the existence and content of international norms. Moreover, looking at implementation, at no time in history has there been more information available to governments and the public about violations of international norms (particularly, but not exclusively human rights violations): more and more these violations are documented through images. Yet, international law doctrines have failed so far to comprehensively assess the power of images, beyond that of a toolkit for thick cultural description – the power of narrative – and analysis. The present essay offers a contribution in this direction.