Thriller films use suspense, tension, and excitement to influence audiences' moods and create uncertainty. There are several subgenres of thriller including psychological thriller, crime thriller, and mystery thriller. Successful examples are films by Alfred Hitchcock. The thriller genre developed from novels and aims to keep audiences engaged by building anxiety through threatening plots and unexpected endings. Popular thrillers like Psycho are influential due to their effective use of lighting, music, and intensity to enhance suspense. Modern thrillers continue to follow these techniques to remain exciting and captivating for audiences.