In a cross-disciplinary investigation of lighting technology and sleep science, I strive to illuminate the ways in which Victorians under the seductive influence and increasing availability of bright city light saw night as a useful space and time. Stoker's Dracula (1897) is a crucial text for examining change in late Victorian nightlife because one of the key determinants of power and powerlessness in Dracula is in the way the body rejects or succumbs to the instincts of sleep. First, I analyse the late nineteenth-century social and medical opinions surrounding technological advances in artificial lighting in order to ascertain the significance of light's apparent effect on Victorians' sleep patterns and sleep quality. Second, I liken the descent from wakefulness into sleep, a state called 'hypnagogia' in sleep science, to the vampiric state of the undead. Dracula holds his victims within the hypnagogic trance to assert his power over them in their weakened and liminal consciousness. My study concludes that Stoker writes men as both strong and weak in their resistance to sleep, and the women as reliant upon the sleep deprivation of men for health and life.