Andrew Detmer (Dane DeHaan) is 17-year-old High School student who lives with his parents in Portland. His mother, Sandra, has Spinal Meningitis, and needs very expensive medication, which Andrew can't afford. His father, Adrian, is a ex-fireman who was forced to retire after suffering a crippling injury, and is abusive towards Andrew and his mother. In an effort to collect evidence to get custody of his mother, Andrew decides to document his day-to-day life with a camera.
One day, Andrew is convinced by his 17-year-old cousin Matt Garrety (Alex Russell) to attend to a party at the abandoned Haven Hills farm. There, he meets Casey Letter (Ashley Hinshaw), a 16-year-old girl who also films everything for her blog. While they're talking, a drunk partygoer approaches Andrew and humiliates him for seemingly filming his girlfriend dancing.
Andrew goes outside to cry, and is approached by 17-year-old Steve Kazinsky (Michael B. Jordan). Steve tells Andrew that he was in the woods smoking weed with Matt and a few others, and they found a hole in the ground making a noise that almost sounds like a whisper. They want Andrew to film it. Andrew goes there with Steve and finds Matt. The others have left. He tries to film the hole, but whatever is inside causes interference to his camera. They decide to investigate and, after going through a long tunnel, they find a crystal-like object embedded to a wall. It produces beacons of light upon touch. Each one of them is exposed to the lights. Finally, Andrew's camera short-circuits.
Two weeks later, Andrew starts documenting everything again with a new camera. Steve, Matt and him have developed telekinetic powers, which they are training. Andrew is the strongest of the three, but Matt is more creative in finding new uses to his abilities. The happening has brought them closer, and they've become best friends. Steve talks to them about his parents' marriage problem and expected divorce, and Matt shares his childhood desire to become a policeman because he wanted to help people.
They start going to Wal-Mart to play pranks on other people with their powers, and, one day, on their way back home, a pick-up truck starts to annoy them. Andrew throws the car off the road and onto the nearby lake with his powers, surprising Matt and Steve. They park by the lake and rescue the driver, who is wounde, but alive. Matt calls the police and the man is hospitalized. Him and Steve then ask Andrew if it was an accident. Andrew claims that it was, and Matt deduces that they're getting stronger, and, therefore, more dangerous, so he creates a set of rules that each of them must follow in order not to hurt other people.
Slowly, the three discover the true extent of their powers. They are able to fly by telekinetically moving their bodies. They can create telekinetic barriers around their bodies that make them invulnerable. And they appear to be connected, being able to "feel" one another from times to times. Andrew becomes popular with Steve's help, while Matt starts a relationship with Casey. Power slowly starts to corrupt Andrew.
One day, Andrew's father finds footage of him at a party and lashes out at him for spending his money on it. Andrew fights back, and threatens to kill his father before flying off. His mother's state has gotten worse, and he decides to film a storm from up close and sell the tapes to TV, as no one has been able to film from such a short distance before. Steve finds out about it and tries to talk Andrew out of it, claiming it's too dangerous. Just as Steve, who confesses that Andrew and Matt are his best friends, suceeds in getting Andrew to turn back with him, he's struck by a lightning and dies.
After Steve's death, Andrew and Matt grow apart. Andrew slowly descends into madness, and claims that, much like the human is the Predator Apex to the other species that live on Earth, he's the human's Predator Apex and his superiority over the rest of the world is matter of survival of the fittest. He starts abusing his powers, and ultimately adopts a "superhero suit" (His father's fireman jacket turned inside-out and a gas mask), and brutally murders a group of small-time criminals that live nearby to steal their money and pay for his mother's medications. However, they don't have enough, so Andrew decides to rob a gas station, but things go wrong and he accidentally causes a bullet fired from a shotgun belonging to the store's clerk to hit a gas tank, causing an explosion that kills several innocents and scars half of Andrew's body.
At the hospital, Andrew's father, infuriated over the expenses he'll have paying for Andrew's recovery, starts to squeeze his open burn wounds while he's comatose. Andrew wakes up and kills his father by tearing him apart limb to limb. He then kills several policemen and members of the hospital staff, and goes on a killing spree throughout Portland, destroying everything and killing everyone he comes across.
Matt sees this on TV and, realizing that Andrew has gone mad, confronts him in Portland. Through a series of cameras (Journal cameras, security cameras, cellphone cameras, etc), we see their violent and destructive confrontation, which appears to end when Andrew breaks Matt's back. However, as he prepares to kill at least 50 policemen who surrounded him, Andrew is impaled by a piece of shrapnel hurled by Matt, who then uses a bullet lodged in his hand to pierce Andrew's skull, killing him.
Matt is captured by the army and taken to a military outpost, where he is left to drown in his own blood while men in containment suits check him with radiation scanners. Suddenly, Matt flungs the men away and rises, his entire body healing itself from a series of injures that include his damaged spines. Completelly unscathed, Matt orders the men to turn off the cameras.
Two years later. South Korea. A huge dam is about to burst and destroy an entire village. A young South Korean boy is filming his father's desperated attempt to leave when the dam ruptures and a huge flood of water advances on their direction. However, it stops moments before hitting the village and is reverted back to the dam, which is the fixed by Matt. He has become a full-fledged superhero and is helping people as he always wanted. After saving the village, he flies away as the villagers cheer for him.
Cut to black.
