peripeteia
1. [ noun ] a sudden and unexpected change of fortune or reverse of circumstances (especially in a literary work)
Synonyms: peripety peripetia
Examples:

"a peripeteia swiftly turns a routine sequence of events into a story worth telling"

Related terms: surprise
Similar spelling:   peripetia
  peripety
  peripteral
  peripatetic
  perpetual
  peripatus