Enigmas

This refers to a puzzle, something mysterious or inexplicable, or a riddle or difficult problem.
In thrillers this is commonly something which the protagonist has to try to find out or solve before the narrative is resolved and the films finishes.

Narrative- Structure, formulas and devices

For example:
Automatic use of 'continuity editing'.
The clear establishment of 'cause and effect' plotting which establishes character motivations and helps tell and interesting story which proceeds logically and steadily.

The 'Pychological' Thriller

The suspense created by pychological thriller often comes from two or more characters preying upon one anothers minds, either by playing deceptive games with the other or by merely trying to demolish the others mental state.
Sometimes the suspense comes from within one solitary character where characters must resolve conflicts with their own minds. Usually, this conflict is an effort to understand something that has happened to them.

Hitchcock 'Maguffin'

A Macguffin (sometimes McGuffin or Maguffin) is ba plot device that motivates the characters and advances the story, but has little other relevance to the story.
'We have a name in the studio, and we call it the 'MacGuffin'. It is the mechanical element that usually crops up in any story. In crook stories it is always the neck and in spy stories it is always the papers.'

Rope (1948)

One of the clips we watched in class was from Alfred Hitchcocks film Rope. It tells the story of two young, wealthy man, Brandon and Philip. The 2 men murder their best friend just to see if they are able to get away with it. They then invite other close friends ( incuding the murdered man's parents) to their appartment for a dinner party, whilst hiding the body in a chest box in their sitting room, just to see if they can get away with it.
The suspense is created through the body in the chest box.