Greg Wittle, portrayed by Owen Wilson, finds himself lost in a haze of daydreams and doodles during his work hours. After getting fired, he envisions a disastrous scenario where he unintentionally kills his boss, Bjorn, played by Steve Zissis, and awkwardly hides the body behind the office curtains. With the day spiraling out of control, he retreats to a nearby bar, where fate introduces him to Isabel, a mysterious homeless woman, played by Salma Hayek. Isabel seems eerily aware of Greg's actions.
As they converse, Isabel elaborates on how she inadvertently shaped this reality and implores Greg to stay out of the police's sight, leading him to abandon his family. With a touch of desperation, she even sells off Greg’s belongings. Tucked away in a makeshift homeless shelter, Isabel introduces Greg to her range of peculiar mind tricks, including the ability to manipulate fire with telekinesis.
Greg starts sharing his artistic visions with her, and intrigued, Isabel offers him a substance that enhances his imagination. This yellow crystal allows him to explore new boundaries of perception, as he fluctuates between the real world and vivid hallucinations. However, as Greg slides deeper into this fantasy, he grapples with the disorienting notion of time while navigating the chaotic streets.
After a comedic yet chaotic encounter at a roller rink, where they envision themselves tripping a bully with their newfound powers, the police arrive, leading to Greg’s unexpected arrest. Meanwhile, his daughter, Emily, portrayed by Nesta Cooper, is on a desperate mission to find him. In her relentless search, she gives him her phone number, hoping to reconnect.
Upon awakening in Isabel's tent one morning to an unsettling absence, Greg finds their shared dreams mirrored in his artwork scattered around. He stumbles upon Emily’s number and calls, only to reach her voicemail. When Isabel reappears, her fury erupts at the thought of Greg contacting Emily, claiming she isn't real. Despite Isabel's manipulations, Greg is adamant about needing proof of reality. In an attempt to demonstrate the truth of their existence, Isabel devises a plan involving special blue crystals, needing ten each to break free from their imagined reality.
What follows is a surreal twist as Greg awakens in a laboratory setting, where he learns about the ‘Brain Box’—a simulation designed by Isabel to examine alternate realities and their psychological impacts. She reveals their intimate connection within this realm and shows him how the world around them has transformed thanks to advancements in science and technology, eradicating many global issues.
As a glamorous gala celebrates the Brain Box, Greg encounters a vision of his daughter, compelling him to choose between his simulated existence and reality. The boundaries between the two worlds begin to blur as Isabel, increasingly frantic, organizes another trip into the simulation to acquire more blue crystals.
However, fate takes a dark turn when Kendo, Greg’s supplier of crystals played by Ronny Chieng, is shot unexpectedly. With police on their backs and choices narrowing, the dire situation reveals that only one of them can escape using the remaining crystals. A selfless decision leads Greg to a poignant conclusion as he urges Isabel to escape alone, despite her protests, to ensure his daughter remains safe in the real world.
Following a tense standoff, Greg finds himself in a rehabilitation clinic, finally awakening to the truth of his feelings for Emily. The story concludes with the promise of reconnection, a reunion built on the foundations of belief, courage, and the freeing power of love.
