Jake (William Moseley) is a dedicated police officer who, along with his wife Prang (Urassaya Sperbund) and their young daughter Loo, sets out on a family vacation to Bangkok. While trying to enjoy a break from their daily lives, Jake's mind remains preoccupied with work matters, leading to some tension in his relationship with Prang, who desires a peaceful holiday free from worries. Their trip takes an unexpectedly dark turn when they become victims of a devastating mass shooting at a busy shopping mall. During the chaos, Jake confronts the attacker, a mysterious and threatening figure named Mek (Michele Morrone), who cryptically refers to Jake as “the Keeper” before triggering a deadly explosion that claims both their lives.
However, Jake's story does not end there. He finds himself in a strange, liminal realm called The Hindrance, a sort of between-worlds space that exists between life and the afterlife. This realm appears dark and confusing, yet it is filled with strange encounters and revelations. There, Jake meets Chan (Alexander), a novice monk who explains that Jake’s death was part of an ancient ritual designed to open the Gates of Hell. Chan reveals that Jake is destined to be the Keeper, a prophesied figure meant to prevent the impending apocalypse caused by the opening of these gates. As Jake grapples with this new destiny, back in Bangkok, Prang and Loo are caught in a city overrun by possessed, zombie-like individuals, and they seek refuge in a hotel while unaware that Mek, who now possesses Jake’s body, is stalking them with malicious intent.
Using a sacred relic—a flintlock and a Nona metal knife given by Chan—Jake manages to return to the physical world by inhabiting another man's body. This resurrection is accompanied by fierce combat as Jake faces Mek, now merged with his own body. The fight is brutal and intense, culminating in Jake overcoming Mek. During the chaos, Prang, confused and distraught by Jake's changed appearance, mistakenly sees him as an imposter and shoots him. The real Jake is subsequently pulled back into The Hindrance, where Chan heals him and prepares him for an inevitable final showdown.
Guided by a map left by Mek, Jake and Chan track down the Gates of Hell, which are ominously close to being fully opened. They discover that Mek intends to sacrifice Loo, whose blood is the key to unlocking the gates completely. In a harrowing climax, Jake kills Mek, whose soul is then destroyed in The Hindrance. Meanwhile, Wichien (Bloom Varin), the father of Wichien and a primary orchestrator behind the ritual, tries to kill Loo, but Prang intervenes by shooting and foiling his plan. Wichien warns that the only way to close the gates is for Jake himself to enter them, sealing the boundary between the worlds forever.
Accepting his destiny, Jake makes the ultimate sacrifice, bidding farewell to his family and stepping into the infernal portal to shut the gates once and for all. With the danger vanquished, Prang and Loo reunite with Prang’s mother, believing that the nightmare has finally ended. However, in a final, unsettling turn, a mysterious woman appears at the site of the sealed gates, hinting that the ongoing struggle between good and evil is far from over—and that the forces of darkness may yet rise again.
