Psychological Thrillers

A psychological thriller is a film that deals with suspense by getting into your mind. Instead of just being about blood and gore, the plot focuses on how the mind can be disturbed and horrified. These psychological thriller films may have lots of action and some blood, but the main intent is the element of the psyche.

A good example of a Psychological thriller is Zodiac.
Zodiac is based on a true story about a serial killer in San Francisco, a yet unsolved crime today. The killer sends messages to the newspaper. The cartoonist from the newspaper is able to help crack the codes the killer uses in his messages. The killer haunts the mind of the reporter so badly that he ends up leaving his job.