This ultra-low-budget film (made for $7,000) takes the premise of shlock like "Cellular" and redeems it with a pinch of Third World travelogue and a twist of Islamist terror. Ian Gamazon and Neill Dela Llana's briskly intense "Cavite" efficiently escorts us from San Diego -- where thirtysomething Filipino-American Adam (played by co-director Gamazon) works as a security guard -- to the Philippines. On deplaning in Manila, Adam discovers a series of photographs and a cell phone in his carry-on bag, and a voice on the other end instructing him how to proceed if he wants to save his mother and sister. "Cavite" is a tense thriller that thrives on its exploration of profoundly unfamiliar territory -- the shanty towns and bustling avenues of the Philippine city of Cavite.

As Adam progresses ever further toward the heart of darkness, guided only by the alternately hectoring and flirtatious voice of the anonymous representative of the murderous Abu Sayyaf Islamist guerrilla group on the other end of the phone, the film never relents from its murderous pace. "Cavite" is much more than a popcorn film for the art-house audience, though; in its central relationship, between Adam and the disembodied, omniscient voice on the telephone, it documents the steady erosion of Adam's ability to make decisions for himself, forced as he is by the threat to his family to cede control over his actions. The film is a tender, unflinching look at the brutal conditions of life in the Philippines, its sympathy for its accidental subjects intertwined with a flexible, on-the-fly mode of filmmaking. The only drawback here is an unnecessary coda that does little to explain the fully contained narrative of the film, and feels both tacked on and not entirely believable. Nonetheless, "Cavite" is true to the statement of its central tormentor: "This is the reality of the Philippines." Starring Ian Gamazon and Dominique Gonzalez. Directed and written by Ian Gamazon and Neill Dela Llana. Produced by Ian Gamazon, Neill Dela Llana and Quynn Ton. A Truly Indie release. Drama. Unrated. Tagalog- and English-language; subtitled. Running time: 80 min