Plot
In December 1977, Jake Van Dorn, a devout Calvinist businessman and single father from Grand Rapids, Michigan, faces a parent's worst nightmare when his teenage daughter, Kristen, vanishes during a church-sponsored trip to Bellflower, California. Months pass with no leads until May 1978, when Andy Mast, a brash private investigator from Los Angeles, presents Van Dorn with shocking evidence: an 8 mm stag film purchased in a Los Angeles sex shop, depicting Kristen engaged in a sexual act with two men. Horrified, Van Dorn becomes convinced his daughter has been kidnapped and forced into pornography.
Flying to Los Angeles, Van Dorn confronts Mast, only to find him distracted by a porn star he was meant to investigate. Disgusted, Van Dorn fires him and takes matters into his own hands. He plunges into the city's seedy underbelly, visiting peep shows, brothels, and adult stores, but his rigid morals clash with the exploitative world he encounters. Frustrated by the LAPD's indifference, he poses as a pornography producer, placing an ad in the Los Angeles Free Press to lure potential informants.
Respondents flood his motel room, including "Jism Jim," a disheveled actor from the stag film. After a violent interrogation, Jim directs Van Dorn to Niki, a streetwise prostitute who claims to know Kristen's whereabouts. Though wary, Van Dorn pays Niki to guide him through California's porn circuit. Unbeknownst to him, his brother-in-law Wes rehires Mast, who tails the pair as their search intensifies.
Their uneasy partnership leads them from Los Angeles to San Diego and eventually San Francisco, with Van Dorn and Niki slowly bridging their ideological divide. Niki, accustomed to being objectified, finds unexpected respect in Van Dorn's company, while he confides in her about his failed marriage and emotional detachment as a father. Their discussions reveal stark contrasts in their views on religion and sexuality, yet mutual dependence grows.
In San Francisco, Niki connects Van Dorn to Tod, a dealer linked to Ratan, a sadistic sadomasochistic pornographer rumored to produce snuff films. In a dimly lit sex shop, Van Dorn endures a screening of Ratan's latest film—a gruesome murder of a Mexican sex worker in Tijuana—traumatized, yet relieved to see the victim isn't Kristen.
Pressure mounts as Van Dorn demands Tod's address from Niki, who fears abandonment once Kristen is found. A heated confrontation culminates in Van Dorn striking her, forcing her compliance. Tracking Tod to a bondage dungeon, Van Dorn brutalizes him into revealing Ratan's hideout: a nightclub hosting live sex shows. There, Van Dorn discovers Ratan and Kristen in the small audience watching two performers on stage.
A brawl erupts as Van Dorn confronts Ratan, who slashes him with a knife before escaping from the nightclub into the street. Mast, who has yet to enter the club, attempts to apprehend Ratan. After struggling to draw his weapon, Mast shoots Ratan who dies in the entrance of a porn theater. While onlookers watch in horror as the police arrive. In the aftermath, Van Dorn finds Kristen cowering in the club's basement. To his devastation, she reveals in anger she fled voluntarily, rejecting his stifling upbringing for a world where she felt seen. Tearfully, Van Dorn admits his emotional failings, rooted in his austere faith, and pleads for reconciliation. Reluctantly, Kristen agrees to return home.
As they depart, Van Dorn spots Niki in the crowd. He attempts a hollow gesture of gratitude, but both understand their bond is severed. Niki disappears into the shadows, resigned to her bleak reality, while Van Dorn and Kristen retreat to Grand Rapids—their futures uncertain, their wounds far deeper than flesh.