1. The Exorcist (1973): Directed by William Friedkin, this classic horror film tells the story of a young girl possessed by a demonic entity and the efforts of a priest to perform an exorcism.
2. The Shining (1980): Adapted from the novel by Stephen King, this film directed by Stanley Kubrick follows a family's stay at an isolated hotel with a dark history, leading to psychological horror and supernatural phenomena.
3. Halloween (1978): Directed by John Carpenter, this slasher film introduced the iconic character of Michael Myers and his terrifying pursuit of a teenage girl on Halloween night.
4. Psycho (1960): Another classic from Alfred Hitchcock, this movie revolves around a serial killer hiding in plain sight at the Bates Motel, creating suspense and psychological tension.
5. The Texas Chainsaw Massacre (1974): Directed by Tobe Hooper, this gruesome horror film follows a group of friends who encounter a cannibalistic family in rural Texas.
6. Rosemary's Baby (1968): This Roman Polanski-directed film tells the story of a young woman who becomes pregnant with the child of the devil, resulting in a blend of horror and psychological drama.
7. The Thing (1982): Directed by John Carpenter, this sci-fi horror movie takes place in Antarctica, where a group of researchers face an alien creature capable of assimilating and imitating living organisms.
8. Hereditary (2018): This critically acclaimed horror film directed by Ari Aster explores themes of grief, trauma, and the supernatural, telling the story of a family haunted by a demonic entity after the death of their grandmother.
9. The Conjuring (2013): Directed by James Wan, this movie is based on the real-life experiences of paranormal investigators Ed and Lorraine Warren, who help a family terrorized by dark forces in their haunted farmhouse.
10. Paranormal Activity (2007): Found footage horror film directed by Oren Peli, which presents a haunted house scenario captured through security cameras, creating a sense of realism and intimacy with the characters.
It's worth noting that the most terrifying movie for one person might not be as scary for another, and the perception of fear can vary based on individual tastes and sensitivities.