Programmer Caleb (Domhnall Gleeson) is at work when he wins a competition to spend a week with the company's CEO Nathan (Oscar Isaac) at his estate. Odd and reclusive, Nathan is a genius who has been working on a secret study of artificial intelligence and has chosen Caleb to be a part of an experiment. He is expected to evaluate a female android, Ava (Alicia Vikander), and decide if she has a consciousness, but things are not as black and white as he first is led to believe.
The film starts by plopping you right into the meat of the story with Caleb dropped into Nathan's world without much explanation of why other than he won a competition. He has no idea what's coming, and with only that lead up, it helps to make the audience feel as Caleb does. Caleb is not quick to trust the strange and obscenely rich man, who is very unnerving and suspicious at times, which makes you question everything, including even the basis of the test.