Persona
This is a seminal (pun intended) masterpiece that will leave an indelible mark on my psyche.
Ingmar Bergman really cooked with this. A dive deep into a broken mind propelled by an undeniable mastery of storytelling, screenwriting and vision from Bergman. He's backed up by a masterclass in lighting and cinematography from Sven Nykvist and in editing from Ulla Ryghe. Bibbi Anderson and Liv Ullman both some of the emotionally deep performances I've ever seen (both of them might make my top 10 greatest performances of all time). All of this contributes to a film that expertly takes the viewer on an emotional roller coaster through fear, anguish, intrigue and so much more. It's also incredibly thought provoking.
My initial, spoiler-free interpretation of the film is this: Alma and Elisabet are the same individual. (I personally don't think it's worth debating whether they exist as two entities purely in a symbolic sense or their psyche is actually split into two different personas because I don't think it changes anything.) They live on the verge of suicide, Alma voices their shame and fear and emptiness, while Elisabet's eyes hold all of their self-hatred and their morbid obsession with death. They want to die, because of what they've done and because of what they have or haven't felt. They want to die but are too afraid to do it to themself. It is entirely possible to want to die, to hope for death and still fear it.