Those who know me know I love a good, disturbing, psychologically-complex film, and Ingmar Bergman's Persona is one of the best. I first saw it as part of a SFMOMA film series in conjunction with their 2007 Jeff Wall retrospective where the artist picked titles that influenced his art practice, and while watching it again this week I remembered how it instantly imprinted itself on my psyche. I imagine that Wall chose the film for the incredible cinematography by Sven Nykvist, as each and every shot is a miracle of light and composition, and for the way that Bergman and Nykvist reveal the process of filmmaking itself as a means of highlighting the descent into madness experienced by Bibi Andersson's Alma. Her character is fascinating, a nurse tending the silent-but-otherwise-healthy Elisabeth at a secluded summer cabin who finds her personality merging with that of her charge. Elisabeth herself is played by the incomparable Liv Ullmann in a performance that is rich with nuance and emotion despite her lack of speech, and Bergman said that it was on this film that he fell in love with her (it's easy to see why). As the flame flickers out at the end plenty of unanswered questions remain and we even doubt the veracity of everything that has gone before. The whole film stands as a enduring metaphor for the utter mystery of the human condition.