Seventeen-year-old Nyah Parks lost her dad and brother in a drunk driving accident almost two years ago. Her mother survived the crash but continues to deteriorate due to brain damage. Nyah has learned about some clinical trials on brain function that could potentially help Mom. The cost to get her into the program is a steep $250,000, of which Nyah has saved about half.
Nyah is a genius computer hacker. She’s made a good portion of her savings by hacking into companies’ computer systems, then offering to show them how she did it and how she can fix their security problems. She grows more desperate as Mom gets worse, and she decides to hack into a large, secretive corporation called BlakBox. With the help of a younger friend, Pixel, she hacks the system and inadvertently discovers images implicating BlakBox in serious illegal activity. When BlakBox executives realize she and Pixel have extracted some of their files, they vow to eliminate the kids.
Nyah goes to Austin Hartt, the only person she believes can help her get the money she needs. Austin is slightly older than Nyah, and his genius far surpasses her own. She met him in her mom’s doctor’s office, where he was being treated, unsuccessfully, for a brain tumor. They began spending time together until Austin stopped returning her calls. Nyah finds him in his apartment, which is hidden in the midst of old warehouses. She’s shocked to learn he has spent the millions he’s made from hacking to purchase medical and scientific lab equipment.
Austin looks sleep-deprived and emaciated, and he has had holes drilled in his skull for the purpose of self-experimentation. He shows her his elaborate computer equipment and water-filled sensory deprivation tanks. He tells her that he has discovered a way to hack into his own brain the way one would hack into a computer. At first, Nyah thinks he’s lost his mind. He begs her to stay and help him with his experiments. As he explains them to her, she begins to see his research could impact her mother’s brain deterioration as well. Austin believes if he can tap into another plane of consciousness and somehow rise above the natural laws by which people live, he may be able to heal his brain tumor. Specifically, he’s looking for a man named Outlaw whom he met several years earlier during a strange out-of-body experience.
Nyah agrees to help, which involves shaving her head and allowing Austin to drill holes like his own in her skull. Separately and together, they hack into their brains by injecting themselves with a synthesized catalyst while they float in Austin’s sensory deprivation tanks. Austin’s computers monitor their brain activity and time their sessions. Each second they spend in the tank in a Hack feels like a minute, and they are able to mentally travel to far off places beyond their present realities.
FBI agent Jill Corbis calls Nyah and says Pixel was found dead. He had heroine in his system, and more of the drug was found in his home. Nyah knows her 14-year-old friend wasn’t a drug user and realizes her life may be in danger, too. She goes to meet Jill, who places an ankle monitor on her for her protection. Nyah manages to cut it off and returns to Austin’s.
While in a Hack, Nyah sees a vision of her mother two weeks in the future, dying of a blood clot. She calls her grandmother Lettie and makes her promise to have the doctors do an MRI on Mom. The MRI does show a blood clot, and doctors begin to treat it. In another Hack, Austin finds the mysterious Outlaw in a jungle. They have a discussion about the nature of reality. While Austin has always believed that the world is knowable through science and the mind, Outlaw tells him we can only know things in part right now. You are not your mind or your body, he tells Austin, but you are an eternal thought held in the mind of the Creator. Just as he did in their previous meeting, Outlaw urges Austin to deditio, to surrender everything he thinks he knows.
Nyah finds herself in Calcutta, India, in another Hack. A little girl tells her to save Mom and urges her not to be afraid of what’s ahead. The little girl touches the scar on Nyah’s head that came from a car accident, and it heals completely. She says Nyah’s scars are not who she is; they do not define her. When Nyah wakes up, she tells Austin she has to go to her mother. Austin realizes they’ve made a breakthrough when he sees Nyah’s head. He urges her not to leave, reminding her people are after her. She risks it and meets back up with Jill, who takes her to the hospital to see Mom. A man named Stone from BlakBox is still following Nyah, planning to kill her. Alone in the hospital room, Nyah quickly gets her mother into a wheelchair, steals Lettie’s car keys and escapes with Mom to Austin’s. When Jill returns to Mom’s now-vacant room, Stone shoots and kills her. He then heads to Austin’s to find Nyah.
Meanwhile, Austin has overmedicated himself in a desperate attempt to Hack longer than ever before. He has a vision in which he is enveloped by God’s light, peace and love. He’s overwhelmed and realizes how much more powerful God is than his own thoughts and mind. He feels gratitude and ecstasy he’s never known. Nyah, too, goes back into a Hack long enough to talk to her mother and learn Mom is dying. Mom says Nyah saved her by getting her out of the hospital and letting her die in peace.
Mom urges her to help Austin now. Out of her Hack, Nyah sees that both Mom and Austin are dead. She tries to revive Austin, first with a defibrillator and then with medication to restart his heart. Stone comes in and shoots at her, asking her where she’s hidden the data she stole from BlakBox. Stone tries to drown her in one of the sensory deprivation tanks. Austin, who has come back to life, shoots Stone and saves Nyah.
BlakBox’s crimes receive extensive media coverage, and the FBI offers Nyah and Austin jobs as hackers for them. Austin’s tumor miraculously disappears. He finally realizes that death isn’t the end of everything and that true reality is far greater than the human brain can comprehend. He has learned to surrender. He and Nyah look toward a brighter future.