Thanks to the movies, I know to be immediately suspicious if I am ever invited to the secluded home of an eccentric billionaire genius. Unfortunately, Caleb (Domhnall Gleeson), a young computer programmer, has no such predispositions when he wins a contest at work that allows him to spend a week with the company’s CEO, Nathan (Oscar Isaac). Caleb is flown deep into the mountains, and at one point asks the helicopter pilot when they will be getting to Nathan’s estate. “We’ve been flying over it for two hours,” the pilot tells him.

Ex Machina, the engrossing new science fiction thriller from writer/director Alex Garland, takes place exclusively in the home of Nathan, a brilliant programmer, rich beyond belief, and living seemingly alone in his house built into the mountainside. Nathan is eccentric, but not played as expected by Isaac. He has the conversational rhythms of a frat boy with the build of a cage fighter, he drinks heavily every day, but beneath the facade is a mastermind. The vibe is immediately threatening when Caleb arrives, and before long he is told why he “won” the contest. He is here to administer a test to Nathan’s new creation, Ava, a robotic organism who may or may not have conscious artificial intelligence. Caleb’s observations will help Nathan decide whether or not he has succeeded.

Ava, played by Alicia Vikander, is about 80% robot with a human face, hands, and feet. She stays in a room while Caleb remains on the other side of a glass box, conversing. The discussions are benign for a while, playful from Caleb as he is overwhelmed with excitement at this groundbreaking revelation. Ava shows glimpses of A.I., but Caleb isn’t sure how much is honest and how much is manipulation from Nathan. Because, it appears, Nathan is not entirely truthful.

Nathan seems to know everything going on in his house, a cold modern-art setup with all the implementations of modern surveillance technology. Cameras operate everywhere under the eye of Nathan, that is, except for these strange power cuts. But beyond his all-seeing eye, Nathan works to control Caleb in conversations, remaining aggressive enough to manipulate discourse in his favor. Isaac creates a fascinating character in Nathan, both threatening and charismatic enough to keep the audience off balance, and on guard.

Things begin to unravel, as expected. As Alex Garland weaves this complex morality play together, paranoia and tension grows to a fever pitch. Is Nathan lying to Caleb? Is Ava truly cognizant of her intelligence? I won’t say anymore here, because the twists are vital to enjoy the film. While there are no sweeping revelations, there are twists in this tale, albeit subtle twists that propel us to the final moments where interpretations are open ended.

Ex Machina is something rare, an adult thriller here at the launching pad of the summer movie season. It is a refreshingly original take on a familiar story, i.e. the eccentric millionaire and artificial intelligence. Oscar Isaac dominates the film, and embellishes in a fascinating dance sequence in the middle of the film that seems to spring from nowhere. But Gleeson, as the impressionable Caleb, is not without his moments. As for Vikander’s work as Ava, hers is perhaps the most difficult. She remains robotic enough to keep the story in tact, but she must inflect moments of humanity to keep us guessing. It is a subtle and well crafted, as is everything else.