It is all in dialogues, conversations. A zero action movie that has no fighting or hints of violence inside. It is a very pure test to the Sean Penn and Dakota Johnson in all acting skills without CG or effects. Check their actings in eyes and that is the best part.
Hint of sex and so the words are inside. I am glad they keep it and make it complete, instead of correctings that lost the likeliness of reality.
Interestingly , I wonder if it could be a stage play later, hope to see it .