Elliot Kintner, portrayed by Paul Rudd, and his teenage daughter Ridley, played by Jenna Ortega, embark on a trip to the opulent estate of Elliot’s employer, Odell Leopold, represented by Richard E. Grant. The journey begins with Elliot battling an allergic reaction, while Ridley appears unfazed and disengaged from the travel experience.
As fate would have it, their road trip takes a strange turn when they accidentally impact a baby unicorn with their vehicle. Stopping to investigate, Ridley is drawn to the glowing horn of the unicorn. In a surreal twist, the horn transports her to a psychedelic world filled with mind-boggling visuals. However, the moment is cut short as Elliot arrives, tragically determined to end the creature's suffering with a tire iron.
Upon reaching the Leopold estate, the duo encounters Odell, who is gravely ill, alongside his wife, Belinda, played by Téa Leoni, and their son, Shepard, portrayed by Will Poulter. While Elliot seeks to finalize a business deal, Ridley grapples with the aftermath of their accident. The unsettling scene escalates when their vehicle begins to shake, revealing the still-living unicorn attempting to break free, only to be lethally shot by Shaw, played by Jessica Hynes.
A chilling transformation unfolds as the onlookers notice that both Ridley and Elliot have been inexplicably cured of their ailments after coming into contact with the unicorn’s blood. Captivated by this miraculous property, Odell mobilizes scientists, including Dr. Song, played by Steve Park, and Dr. Bhatia, portrayed by Sunita Mani, to investigate and harvest the unicorn for medical breakthroughs.
Yet, while Elliot is drawn deeper into Odell's ambitions, Ridley becomes increasingly uncomfortable with how the unicorn is being exploited. Following a successful extraction of the horn’s essence that cures Odell, the plot thickens as Shepard experiments with the horn, leading to a profound connection with the creature that echoes Ridley’s own emotional bond. As a bizarre aurora borealis manifests in the sky, it signals the impending chaos.
The tranquility shatters when a menacing black unicorn crashes the party, violently attacking Dr. Song and leaving destruction in its wake. As Elliot frantically tries to safeguard Ridley, she attempts to connect with the black unicorn, which unfortunately is interrupted by the arrival of armed guards. The unicorn escapes, but not for long; a deadly pursuit ensues into the woods.
Elliot’s quest spirals into a harrowing confrontation with the black unicorn's parents, as the plot unveils the terrible cost of their scientific curiosity. Ridley’s revelation about the unicorn's regenerative abilities adds a new layer of urgency. Nevertheless, the stakes rise further when the adults fail to control the unleashed force of nature, leading to horrifying carnage in their ranks.
As tragedy unfolds, the lines between right and wrong blur dramatically for Elliot. When the black unicorns retaliate with vengeance, multiple casualties emerge, including his colleagues and family. In a gripping climax, Ridley, seeking to mend the rift caused by the theft of the horn, becomes an unwilling pawn in a deadly game orchestrated by Shepard, who envisions dark prospects for the unicorns.
With a fierce struggle punctuated by betrayal and loss, the narrative culminates in a heart-wrenching father-daughter moment as they confront their fate. Just as all hope seems lost, the benevolent unicorns intervene, wielding their mystical powers to restore the fallen. The passage concludes with Elliot and Ridley unexpectedly spirited away, as law enforcement arrives, misinterpreting the chaos as a string of murders.
In a twist of fate, the unicorns make their timely entrance, charging at the cop cars, ultimately leading to the hopeful possibility of reclaiming their peace amidst the horror they endured. As the story wraps up, Elliot and Ridley’s bond is fortified by their extraordinary journey, and they prepare to tackle the mysteries life continues to throw their way.
