It’s an alien movie, but different from other, ordinary alien movies. It’s about contact between human and heptapods getting to understand each other through language.
So I would call this a linguistic movie. Someone has described this as ‘Interstellar of the humanities.’ I believe this metaphor is quite accurate, even though I’ve never watched Interstellar.
There is some weakness in details of the story, but I think highly of the fact that Arrival has focused on the power and function of language which movies have rarely focused on, and I liked the scene with the rhythmical OST ‘Heptapod B.’ It was very original.