Do you arrange movie titles starting with an "A" as A?
Or omitted the "a" and arrange according to the first letter of the second word?
I always put "the" at the end so that my movie collections sorted by the second word instead (e.g., LEGO Movie, The) would be in L and not T, but keep A in front (e.g., A Separation) so that it would still be in A and not S.
Wikipedia uses BOTH (so everything duplicates) in their list of films.
https://en.m.wikipedia.org/wiki/List_of_films:_A
What do you prefer?