Nightmares are one of the privileged expressions of that aesthetic of the horrid which defines the poetics of the Scapigliati and famously inhabit the narratives of Arrigo Boito, Iginio Ugo Tarchetti, Antonio Ghislanzoni, Remigio Zena among others. The dream-like dimension informs the Romantic and Fantastic literature of authors such as E.A. Poe, E.T.A. Hoffmann, Baudelaire (extremely influential for the Italian bohème), and often conveys those anxieties characterizing the advent of modernity. Nightmares moreover evoke different components defining the Scapigliati’s cultural mileu, from anguish to folly to those meanders of the psyche which practices like spiritism help bring to the foreground and investigate. Tarchetti in particular recurred to the nightmare trope not only in his more explicitly fantastic and gothic narratives but also in more realistic, such as Una nobile follia or even utopian ones, “Re per ventiquattr’ore.” This chapter investigates the dimension of the nightmare in these latter works where the trope in question is key to critique political and social policies and practices, from militarism to bourgeois conventions, as well as to anticipate instances which will be further investigated in twentieth-century psychological novels.