In a small German town, at a local fair, a mysterious showman named Dr. Caligari presents his main attraction: Cesare, a somnambulist who has been asleep for 23 years. Dr. Caligari claims that Cesare can predict the future while in his deep, trance-like slumber. The spectacle draws the attention of two friends, Alan and Francis, who are intrigued by the eerie presentation. Feeling curious, Alan decides to ask Cesare how long he has left to live, only to receive a chilling prophecy: he will die by dawn the next day. The town is gripped with fear when the prophecy grimly fulfills itself, and Alan is found dead the following morning, stirring suspicion and setting off a string of mysterious and terrifying events.

Meanwhile, Francis, driven by his desire to uncover the truth behind his friend's untimely demise, embarks on a personal investigation into Dr. Caligari and Cesare. His endeavors lead him to explore the shadowy corners of the fair, the local insane asylum, and the cryptic past of the somnambulist. As Francis delves deeper into the mystery, the townspeople experience an escalating sense of dread, with whispers of more unsettling incidents linked to the dark attractions of the fair. The air is thick with paranoia and suspicion, shrouding the motives of the sinister Dr. Caligari and his seemingly obedient sleepwalker.