Five-year-old Veronica encounters a man named William after tragically losing her parents. He offers her a chance at a new life, one filled with purpose, by training her for a special job. He shares with her his devastating past, detailing how his own wife and child were taken from him by "a very bad man." Seeking comfort and guidance, Veronica willingly accepts his offer.
Fast forward twelve years, and Veronica is on the brink of completing her training. To prepare her for the dire consequences of her future actions, William injects her with a potent mix of truth serum and DMT, a hallucinogenic drug. This is to help her face her deepest fears, as she needs to comprehend what her victims will experience. Although Veronica prides herself on being fearless, she ultimately confronts the fear of failure regarding her mission.
Meanwhile, a group of four teenage boys—Jameson, Daniel, Nelson, and Shane—gather at a diner, where Jameson decides on their next target: a girl named Gwen. The boys take her to the woods, where they commit a heinous act and murder her. During this time, Veronica conducts reconnaissance at the diner and meets Shane's girlfriend, Jennifer. They connect over their relationship struggles, which leads Veronica to divulge her budding romantic feelings for William, notwithstanding their significant age gap and her understanding of his emotional unavailability. Jennifer warns Veronica that the boys' friendship is beginning to fracture.
In a bold move, Veronica uses herself as bait to lure Jameson by accepting a date. With the boys picking her up, they venture back to the woods, where they decide to play a tense game of truth or dare. As part of her plan, Veronica secretly offers the group whiskey laced with the hallucinogen, ensuring that only Jameson remains sober. When she draws the dare to "Die," she pleads to be taken home, but Jameson gives her a mere five-minute head start. However, the boys, driven by bloodlust, can't resist the hunt.
As the drugs start affecting their minds, Daniel is haunted by hallucinations of two panda heads in suits. In reality, it's Veronica who seizes the chance and kills him using his own axe. Nelson sees his deepest fear manifest—being surrounded by faceless figures—and shares an intimate moment with his mother before Veronica swiftly crushes his head with a rock. Meanwhile, Shane grapples with visions of his girlfriend cheating on him with Jameson and begins to doubt their bond.
After discovering Daniel's body, Jameson is intrigued and unnerved. Just then, Shane's girlfriend shows up, and an awkward tension arises as Jameson tries to flirt with her, later revealing their complicated history. Initially resistant, she ultimately succumbs to his advances. Just as Shane arrives and catches them in a compromising position, a confrontation ensues. Jameson desperately wants to reveal their sinister past of hunting and killing girls, but in his moment of aggression, he threatens her with a gun. Shane intervenes, but amid the struggle, Veronica's intervention leads to Shane's unexpected death.
In a climactic showdown, Jameson challenges Veronica to a game of questions where each must answer truthfully. He brazenly admits to killing 21 women, Veronica included, which shocks her. Despite his proposal to join forces, she rejects him, leading to a fierce battle between them. Utilizing a choke-hold technique she learned from William, Veronica forces him into submission. In a twisted turn of fate, she compels him to drink the drug-laced alcohol. When he regains consciousness, he finds himself on a tree stump, a noose around his neck. He pleads for mercy, insisting he won't kill again, but Veronica, having seen the darkness within him, remains unconvinced. As his hallucinations take hold, the spirits of his victims, including Gwen, emerge from the woods, driving him to despair. In a moment of panic, he steps off the stump, ending his life.
Ultimately, William appears, commending Veronica for her actions, and they share a triumphant moment as they head to the diner for pancakes, marking the end of a harrowing journey.
