Parasite (Korean: 기생충) by Bong Joon-ho.
I have loved and respected Bong Joon-ho and his body of work since "Okja" and "Snowpiercer" and he never fails to surprise, delight, and move me every time. So it means a lot to me to be able to say this is his best film. It is.
A movie full of sadness, wit, and depth. Irreverent but benevolent. Amazing.