Opening sequences and Enigma - Memento

Within the opening sequences of Memento, we as an audience are instantly disoriented through the films used of a reverse story telling, this reflects Leonard's ante-retrograde amnesia and fragmented perception of events and reality. The films use of central enigma, who can be trusted, what truly happened and so on, begins to unfold over time, forcing the viewers to piece the events together along  with Leonard. The director, Christopher Nolan, uses this to immerse the audience into the characters confusion, drawing an increased focus on the themes of memory, identity and the unreliability of human perception.