Ex Machina is a film about a young programmer in a big company comparable to Google, who wins a lottery of sorts, which entails him to stay at the Boss's place and be a part in his latest project, A.I.
There aren't many characters in this movie and for a movie like this to be interesting, the few characters HAVE to do a great job. The main dude was the only one who I felt like wasn't that good. Oscar Isaac, who plays the Boss/Genius, was awesome. He wasn't your typical rich/boss/genius douche. The one who stole though was Alicia Vikander, who plays the A.I Ava. She did a great job of depicting a high level artificial intelligence.
Now the movie really doesn't get into much introduction or world building. It actually felt really rushed in the beginning and just takes our protagonist to the place where rest of the movie will unfold. And that MAGIC of A.I was kinda missing. But afterwards, it very slowly starts to create tension. There is nothing but conversations but you can feel the tension building up and up and things often revealed aren't what they seemed. The pacing sometimes did become snail like though. The ending felt somewhat anti-climatic but at the same time, all the slow build up tension got released in the same slow manner and had this really chilling sensation.
Best thing about this movie for me were the questions like What it means to be human? How this technological world defines each and everyone of us etc etc. Stuff like this makes you go deep in thought long after the movie is finished.
I do think that people are really overrating it. A decent sci-fi thriller nonetheless.