7

The first 10 minutes of the movie give us the plot, and the way how the movie is going to end. Everything is in the details as the appearances of the characters or their names.

Shooter is a defense, it helps him to deal with his traumatic experience, his couple crisis. This new identity is created to release the tension from wich Mort suffers.

As we can see there is an turning point event wich caused the mental disorder and allows the director to play with our senses.

It's a popular theme in Hollywood, as such personnality crisis involves a lot of interesting cinematographic elements to hint the struggle between the two identities : for example, the split screen ; the mirror ; the split diopter lens. One of the reason why it's so commonly represented is also that it oftens involves a plot twist at the end of the film, which is a rather popular scenaristic tool.