enigma?

an enigma is another technique that thrillers incorporate to confuse and disorientate the audience so they don't see the final twist coming which increases the entertainment value twice maybe even thrice fold.an enigma refers to a puzzle or something mysterious and inexplicable.this riddle is normally meant to be solved by the protagonist and normally formulated by the antagonist.this is normally resolved by the duration of the narrative but sometimes it is left open to make the audience think an example of this is inception we do not know why the wife of the main character "kob" keeps trying to attack and dismantle his dreams we find out that its because he and his wife were stuck in dream limbo and when they escaped she killed her self because she thought she was still dreaming, at the end of the film we see kobs totem a spinning top start to topple but we never see it fall so we the audience do not know whether the whole film was a dream or not. this is also a good example of a cliffhanger