Ethan, a young biochemist, and his friend Ben are on the rooftop of the family cannabis farm when they receive devastating news: Ethan’s parents have died in a car accident. Four years later, Ethan runs the farm, having become his sister Charlotte's legal guardian. Ethan has spent much of his time developing his latest cannabis strain, the Holy Grail, a plant that can erase fear from anyone who smokes it. But Ethan himself suffers from crippling agoraphobia and is unable to enjoy the very creation he's so proud of. Charlotte, now in charge of the farm’s maintenance, is frustrated by her brother's overprotective nature and his refusal to leave the farm. When she and Ben go out for Halloween celebrations, Ethan’s anxiety drives him into hiding.

Meanwhile, the Holy Grail has caught the attention of dangerous individuals. A group of Yakuza gangsters, led by the Wakagashira, has learned of the strain and intends to seize the cannabis farm. Kiko, one of Ethan's colleagues, has been kidnapped, and when the gang arrives at the farm, they take Charlotte and Ben as hostages. In the midst of this chaos, a trio of assassins — Ava, Ono, and Zez — infiltrates the farm. Ava, who smokes the Holy Grail, gains the ability to think for herself and decides to protect Ethan, revealing that the Yakuza want to steal the plant for their own purposes.

As the Yakuza close in, Ethan is forced to confront his own fears and trust those around him. Ava helps him navigate the farm’s dangers, but tragedy strikes when Steve, a farm hand, is killed. Meanwhile, Charlotte and Ben struggle to escape their captors, with Charlotte managing to evade capture by using her strength in a desperate moment. The Yakuza's plans continue to unravel, as Ethan, Ava, and Kiko join forces to rescue Charlotte and defeat the Wakagashira.

In a tense final confrontation, Charlotte, with the help of Ethan and Ava, defeats the Yakuza, throwing the Holy Grail to outsmart their leader and kill him. The farm returns to normal, and Ethan's desire to travel — something he's kept at bay for years — is rekindled. The journey to Amsterdam looms on the horizon as Ethan finally begins to believe in the freedom he's longed for, both for himself and those around him. The adventure for both healing and exploration has only just begun.