"Ratsasan" is a Tamil-language psychological thriller film released in 2018. Directed by Ram Kumar, the movie follows a determined police officer, Arun, who investigates a series of gruesome murders linked to a mysterious serial killer. The film explores themes of obsession and the psychological impact of crime on both the victims and the investigator. The film received critical acclaim for its gripping storyline, strong performances, and effective use of suspense. Vishnu Vishal plays the lead role, while Amala Paul features as the female lead. "Ratsasan" has been praised for its engaging narrative and has garnered a dedicated fan base.