When young history professor Russ is asked by his sister to sort out their late mother’s estate, he finds himself reuniting with his childhood friend Mike and with his father, a charismatic leader of a New Age cult. As he searches through faded memories, Russ wanders into a warehouse where hundreds of names are scrawled on the walls, hinting at a deeper history tied to the town itself. That night, a surreal vision unfolds: a stone cudgel haunts his sleep, and upon waking he discovers a cudgel inscribed with the word Dagon resting in his motel room. A town drunk warns him that this is an instrument of sacrifice, a grim omen that will pull him further into danger.
A young liquor store clerk pleads for help, asking Russ to locate her brother who she believes has been taken by the cult. This urgent request drags him deeper into the town’s tangled past, and his aunt—living in an asylum—tells him that his mother left a hidden message somewhere in her house. The clues lead Russ to the warehouse, where a journey through the town’s ancient, subterranean roots unfolds, revealing a history that seems to reach far beyond ordinary answers.
When Russ and Mike escape the labyrinth, they discover the girl’s brother murdered, a brutal sign that the cult is already wielding real power. Convinced that a mass sacrifice is being prepared, Russ pursues covert information by courting a seductive figure who can provide crucial details. The path becomes violently personal as he is raped and then arrested for murder on the eve of the town’s May Festival, a chaotic moment that intensifies the stakes surrounding the cult’s nefarious plans.
The danger escalates as Russ learns that the cult intends to seize control of the world by bringing to life anthropomorphic creatures from the sea, a revelation that blends horror with a prophecy-like outlook on the town’s fate. Throughout this perilous quest, the fear for the future of his own family gnaws at him, underscoring the price of truth in a place where loyalty and danger are tightly braided.
In a stark, intimate moment, Russ is shown his children in a bathtub, a domestic image contrasted with the city’s ominous doings. The film reaches its tense climax as Russ and his best friend, who is also his lover, are held by the cult while Russ’s father commands him to sacrifice the man he loves. The tension plateaus into a dangerous hesitation as Russ moves to strike, caught between familial duty, personal love, and the looming threat that could extinguish any chance for safety or salvation.
