Forgot to add a classic,
Starring Tom Cruise, Magnolia...
An absolutely EPIC psychological thriller. Basically you initially follow 8 apparently different characters/storylines, but they are all connected in some way. The film opens in a rhetorical question regarding three cases, all apparently due to "a matter of chance". The movie looks at father/son relationships, issues of fidelity, but the coup de tat is this idea of some sort of cosmic force causing all of these coincidences to occur, linking past to present to future [and our subsequent inability, despite earnest efforts, to escape from the past]. A part of the opening, concerning the three cases (not related to the bulk of the movie) can be seen here:
If you want to be in scratching your head in enjoyment, really recommend seeing this movie...