This paper unearths the archeology of reaction media across cinema, television and the Internet. We show how reaction content exists in high and low modes, tracing their reoccurrence and remediation from art-house and horror in cinema, to television soap opera, to animated GIFS, and YouTube compilations. Because reactions can be readily repackaged and resourced, we argue that they are a form of inter-media; operating in-between media text and media reception; in-between narrative and sensation; in-between authenticity and performativity; and in-between entertainment and resource. Reaction media are a form of sensory media with material properties. The textual and aesthetic richness of reaction content informs their persistent function, allowing for generative repurposing by internet users as a form of cultural expression and also operating as a rich resource of content able to be repackaged by professional content creators for producing economic value.