This article examines how mephedrone, the most popular legal high sold freely in the United Kingdom until its classification as a high-risk drug, in April 2010, was constructed by the British popular media as a moral epidemic that threatened the very symbolic heart of the nation – its youth. News of teenagers committing suicide after taking the drug or dying of overdose had been presented in the pages of tabloid dailies for months when the government decided to ban the substance despite the lack of solid scientific data on the medical and social risks it posed. Drawing on Teun van Dijk’s socio-cognitive approach to critical discourse studies, this article demonstrates how in its attempt to influence national policy the media largely responded to the new drug problem with panic discourses that perpetuated the old ‘war on drugs’ ideology, choosing to frame mephedrone as an agent of death and moral downfall even when its destructive influence was questionable. In this perspective, a blueprint made of multiple layers of historical drug scares and repressive drug policies shaped the metaphors and narratives used by the media to codify a sense of threat and by the audiences to interpret the symptoms of a social pathology.