This paper addresses the issue of the crisis of therapeutic efficacy in Britain through a case study of benzodiazepine tranquilliser dependence. The paper traces the rise of tranquillisers and the crisis of legitimacy in prescribing behaviour in the 1980s. It documents growing concern with dependence and the claims made about it by experts and consumer groups. The paper goes on to analyse the importance of the television in these claims-making activity and its influence in shaping perceptions. Finally, we consider the implications of these events for the future of benzodiazepine tranquillisers as a form of treatment.