This chapter looks at the discursive production of theater as a decadent institution over the course of the fin de siècle in Britain and France, focusing especially on the prevalence of the antitheatrical prejudice at the time. It considers why theater was thought to be inadequate or injurious on the basis of several kinds of impurity, including the pejorative condemnation of its potentially viral degeneracy (moral impurity), critical ruminations on creative sclerosis and declining artistic standards (aesthetic impurity), as well as the reasons why several prominent playwrights and critics of the period who were closely associated with both decadence and symbolism were uneasy about the staging of decadent drama (metaphysical impurity). Moving from a two-dimensional account of theater’s decadence in the hands of moral purity advocates, to a more nuanced consideration of the surprisingly generative qualities of the “Paterian paradox,” the chapter argues that theater’s decadent “wrongness,” especially when it is embodied and enacted, may be the best starting point we have for appreciating its role in a nascent modernism.