Background Long before being described as a disorder, sleepwalking was considered as a mysterious phenomenon inspiring artwork. From the early beginning of cinema, sleepwalkers were shown to populations, playing a crucial role in storytelling and collective knowledge. Objective We characterized how sleepwalking has been portrayed in a large number of movies from the origins of cinema to recent years. Methods Movies containing the words “sleepwalking” or “somnambulism” were searched for in International Movie Databases. Types of movies, sleepwalking characters, postures and behaviors during episodes, triggers, and suggested treatments were collected. Results Production of 87 movies and 22 cartoons portraying sleepwalkers was clustered around two peaks, in the 1910s and 2010s. Comedies predominated before 1960, and thriller/horror movies as a dominant genre after 1960. In contrast with real-life sleepwalking epidemiology, sleepwalkers are more often portrayed as women than men (and often wearing a transparent white nightgown), as adults more than children on-screen, and 23% suffered psychiatric comorbidities. The unrealistic posture of outstretched arms and eyes closed was found in 20% of movies and 79% of cartoons. Night terrors, sexsomnias (kissing, having sex, initiated pregnancy), sleep-related eating and sleep driving were also featured. Homicides and falls while sleepwalking were recurrent fear-inducing topics. The first sleep EEG was featured in a sleepwalking movie in 1985, and a sleep specialist gave his first advice in 1997. Discussion The representation of sleepwalking on the screen seems to have evolved from popular, unrealistic stereotypes of somnambulism towards a medical condition, paralleling the development of sleep medicine.