In ‘The Typology of Detective Fiction’, Todorov distinguishes between the whodunit and the thriller on the grounds that the former is a double story and the latter a single one (2000: 139). The whodunit is double in the sense that it is the story of ‘the days of the investigation which begin with the crime, and the days of the drama which lead up to it’. The simplicity of this observation is matched only by its importance, because it means that the whodunit goes backwards as it goes forwards, or more precisely that it reconstructs the time line of the crime in the time line of the investigation. In the thriller, on the other hand, the narrative coincides with the action in a single story. The experience of reading the whodunit is characterised by curiosity, since it proceeds from effect to cause, whereas the thriller is characterised by suspense and proceeds from cause to effect.

The hermeneutic circle of presentification and depresentification with which I have been characterising the relationship between reading and living can be seen here at work in the relationship between one type of fiction and another, insofar as the whodunnit works backwards from a known outcome while the thriller proceeds forwards into an unknown future.