What's the first movie you saw, that made you realise movies can be different?

It's an awkward wording in the title but I think it resonates when I first saw this question elsewhere.

If you're anything like me (a millennial who grew up in a developed country) you probably started off watching children's movies (perhaps animated movies like the Disney renaissance) or family comedies (Home Alone, Beethoven, etc) and from there into mainstream blockbusters and action movies (Jurassic Park, Die Hard, etc). Maybe you had a cool older person who showed you a horror movie a little earlier than was age appropriate. That sort of thing.

What was the first movie you remember seeing, that you remember thinking 'this is different'? This is special, in some way? This is what 'movie magic' or 'the art of cinema' is?