This article draws upon research from the first ethnographic field study of covert policing conducted in the United Kingdom, and seeks to shed light on how covert officers carry out their surveillance work. In particular, it demonstrates how officers attempt to blend into their surroundings and render their work invisible in order to intrude into the daily lives of those people considered suspect. In so doing, the authors highlight some hitherto unnoticed aspects - or 'invisibilities' - of policing, and show that the surveillance strategies used by law enforcement are increasingly embedded in the most mundane aspects of social life. In contrast to the processes of mass surveillance that are typically the focus of surveillance scholars, the article serves as a reminder that the surveillance powers of the state are vastly intensified when individual members of the public are regarded as suspects by the police. Abstract published by arrangement with Sage Journals.