In the quiet fields of rural Argentina, a single possessed dog unleashes a plague of demonic fury that turns family bonds into fatal curses.

Deep within the Argentine pampas, where isolation breeds unseen horrors, When Evil Lurks (2023) emerges as a visceral gut-punch to the possession subgenre, transforming age-old demonic tropes into a contagious cataclysm.

• How director Demián Rugna reimagines possession as a viral pandemic, blending slasher brutality with apocalyptic dread.
• The film’s unflinching exploration of family fractures amid supernatural siege, anchored in raw performances.
• Its groundbreaking practical effects and sound design that amplify the relentless spread of evil.

When Possession Turns Pandemic: The Ruthless Horror of When Evil Lurks

The Infected Outbreak

In When Evil Lurks, the nightmare ignites with a grotesque discovery: a rotund, shambling figure known as ‘the Rotten’, a man possessed and rotting from within, tended by a local recluse in the remote Argentine countryside. Brothers Pedro (Ezequiel Rodríguez) and Jaime (Demián Salomón), divorced pig farmers scraping by in their decaying rural enclave, stumble upon this abomination while dealing with a marauding possessed dog. What begins as a desperate attempt to euthanise the beast spirals into a chain reaction of infernal contagion. The dog bites a victim, and soon the possession spreads like rabies fused with demonic fury, turning humans into vessels of unpredictable violence. Rugna masterfully establishes the rules early: the possessed do not always attack immediately; they bide their time, feigning normalcy before erupting in savagery. This unpredictability heightens tension, as every interaction becomes a potential vector for doom. The film’s opening sequences, shot in stark, desaturated tones, capture the mundane rot of rural life—muddy fields, rusted trailers, flickering fluorescent lights—setting a stage where evil feels both primordial and perilously close.

The narrative hurtles forward with Pedro and Jaime evacuating their families amid escalating chaos. Pedro’s ex-wife Sabrina (Lucrecia Blake) and daughters Juli (María Jesús Soto) and Nina (Virginia Garófalo) join the flight, alongside Jaime’s pregnant wife Carla (Marcelo Michinaux, no, wait—actually Silvana Daniel as Ruth, but core family dynamics centre on these ties). They seek refuge in a ghost town overseen by Father Prior (Sergio Fonseca), a priest versed in the ‘rules’ of possession: no direct eye contact with the Rotten, no killing them within town limits lest the demon multiplies sevenfold. These folklore-inspired edicts, drawn from Argentine and broader Latin American demonological traditions, ground the supernatural in cultural specificity. Rugna, building on his prior work in Terrified, eschews jump scares for a creeping dread, where the horror lies in the inexorable logic of the plague. As infected townsfolk mutate—eyes glazing over, bodies convulsing in blasphemous paroxysms—the film evokes real-world pandemics, mirroring lockdown isolations and quarantine failures.

Rural Rot and Familial Fracture

At its core, When Evil Lurks dissects the fragility of family under existential threat, using the possession plague as a metaphor for buried resentments erupting violently. Pedro, the more volatile brother, embodies paternal failure; his insistence on returning home despite warnings underscores a macho stubbornness that dooms his kin. A pivotal scene unfolds in a dimly lit kitchen where Juli, the elder daughter, manifests symptoms—her innocent face twisting into a rictus grin as she whispers profane taunts. The family’s hesitation to act, paralysed by love and denial, amplifies the tragedy. Rugna’s camera lingers on these intimate betrayals, employing tight close-ups and shallow depth of field to trap viewers in the emotional vice. Class undertones simmer beneath: the brothers’ pig farm, symbolising their lowly status, becomes ground zero for infestation, critiquing how marginalised rural communities bear the brunt of unseen apocalypses.

The film weaves gender dynamics into its carnage. Women, often bearers of demonic vessels—pregnant Carla’s unborn child possessed, or the vengeful figure of the local woman who started it all—highlight vulnerabilities exploited by the evil. Yet Rugna avoids exploitation; instead, these portrayals interrogate societal roles, with mothers sacrificing amid patriarchal collapse. Sound design plays crucia,l here: guttural growls emanate from wombs, children’s laughter warps into shrieks, creating an auditory plague that invades the viewer’s space. Compared to classics like The Exorcist, where possession isolates a single victim, Rugna’s version democratises horror, making every soul a potential carrier, echoing [REC]‘s found-footage frenzy but in widescreen scope.

Slashing Through the Supernatural

As a ‘possession plague slasher’, the film hybridises genres with brutal efficiency. Traditional slasher elements—chases through fog-shrouded woods, improvised weapons like machetes and rifles—collide with body horror. Victims don’t merely die; they transform mid-attack, limbs elongating unnaturally, mouths unhinging to spew bile. A standout sequence sees a possessed child wielding superhuman strength, hurling adults like ragdolls, her tiny frame belying the demon’s rage. Rugna’s choreography blends balletic precision with gore, influenced by Argentine folk horror traditions where rural superstitions manifest physically. The plague’s rules evolve: proximity to the Rotten accelerates infection, but ‘clean’ kills outside limits preserve humanity’s slim chance.

Cinematographer Maxi Menem’s work deserves acclaim; long takes track the brothers’ desperate road trip, headlights piercing infinite night, evoking Jeepers Creepers but stripped of camp. Lighting favours chiaroscuro extremes—harsh whites in clinics contrasting abyssal blacks in barns—symbolising the battle between sanctity and sin. Production faced real challenges: shot during Argentina’s economic turmoil, the low-budget grit (under $5 million) forced ingenuity, using local farms for authenticity. Censorship battles ensued; the film’s graphic possessions pushed boundaries, earning an unrated release internationally while sparking debates on demonic realism in Latin cinema.

Effects That Linger Like a Curse

Practical effects anchor the terror, courtesy of a team led by Rugna’s collaborators from Terrified. Prosthetics depict decay with meticulous horror: skin sloughing in translucent layers, eyes bulging from sockets, achieved via silicone appliances and corn syrup blood thickened for viscosity. No CGI crutches; a possessed dog’s convulsions used animatronics, its jaws puppeteered for visceral snaps. The ‘flaying’ sequence, where a victim’s flesh peels autonomously, employs reverse-motion puppetry, a nod to early Cronenberg. These effects not only shock but symbolise moral putrefaction, the plague stripping humanity layer by layer. Soundscape complements: wet crunches, laboured breaths layered with infrasound pulses induce nausea, as per studies on auditory horror immersion.

Legacy ripples outward; When Evil Lurks premiered at Sitges 2023, clinching best picture, influencing discourse on ‘New Argentine Horror’. It bridges Terrified‘s poltergeist chaos with global plagues like , positing demons as equal-opportunist pathogens. Fan theories proliferate: is the plague biblical, tied to Revelation’s locusts? Rugna demurs in interviews, favouring ambiguity.