Memento

This film is about a man named Leonard Shelby (Guy Pearce) who has anterograde amnesia which stops his ability to store new memories in his brain. He developed a way to recollect his memories by writing down notes, taking photos, or even getting tattoos of his memories on himself for him to solve the puzzle when he forgets. This film is portrayed through a black and white series that is in alphabetical order in time and then another series of color film where the memories are reversed in time. At the end of the story the two themes meet at the end producing one story: finding the second culprit who raped and murdered his wife. 
At the end of the movie, you find out that Lenoaerd thought his life was the life of a man named Sammy Jankins and finds out that his wife was killed from an insulin overdose.
This movie was incredibly hard to understand but was really entertaining too watching,  think that the event that were in color or reversed got Leonard confused of who was the real "John G". This movie was a great perception of time in itself and helped me as a viewer understand the concept of time.