Michael Winterbottom is an intriguing and often eloquent director, who can move easily from large-scale productions like the under-rated “Jude” and the more problematic but visually striking “The Claim” to rougher, more quasi-documentary fare like “Welcome to Sarajevo” and this film. “In This World” is a harrowing snapshot of people-smuggling from the Third World to the developed one, a stark depiction of an attempt by two Afghan cousins to make their way illegally from a Pakistani refugee camp to England. Though it occasionally gets too didactic–particularly in the narration toward the start and some general statistics elsewhere–when it hits its stride, it’s almost like a modern version of one of De Sica’s neo-realist classics from the fifties.

The picture, shot on high-definition video, gives an appropriately gritty look to the journey that the two men–the older, slower Enayat (Enayatullah) and the younger Jamal (Jamal Udin Torabi), who has some useful linguistic ability–take at the encouragement of their family. The narrative first introduces us to the camp in Peshawar where the refugees live, and then briefly shows the negotiations which result in a payment to the arranger of transport. Soon they depart on an overland route through Iran, Iraq and Turkey, constantly trying to link up with the next facilitator on their schedule while avoiding capture by border guards. The next leg of the journey is a dangerously confined trip in a ship’s hold to Italy, which has tragic consequences, followed by a stay in a French camp prior to the final passage to England; the fate of the survivor once the destination is reached provides a sadly ironic conclusion.

What makes the experience of Jamal and Enayat so wrenching is the precision and detail with which it’s recounted. Curiously, the loose, episodic character of the narrative is what gives it special power. One doesn’t get the sense that things have been arranged for dramatic effect; instead there’s a feeling of naturalness in the almost painfully uncertain succession of events as the travelers sometimes meet with kindness and on other occasions with either harshness or simple unconcern. The various characters are portrayed well, too: the cousins are depicted sympathetically, but at the same time are kept down-to-earth, showing for instance a degree of reasonable suspicion toward almost everyone they encounter. (The cast, composed of non-professionals, is quietly effective.) And the sense of place is palpable. The cast and crew, we’re told, actually took the trek shown here, preceded by the producer, who arranged things for the next scene just before their arrival at each location.

“In This World” is hardly a joyously uplifting experience; it doesn’t become one of those mawkish fables of the indomitability of the human spirit that most fiction films, even on difficult subjects, usually turn out to be. Its purpose is to depict poverty and desperation of a sort that most of us rarely think about, let alone experience even vicariously; and while we may admire the hope and perseverance the cousins exhibit, the picture never deludes us into believing that they will be enough. And while there are moments when its agenda threatens to overwhelm things, Winterbottom skillfully skirts easy didacticism in favor of a more subtle approach. His film tells an important story in a genuinely moving and realistic fashion. This second feature in the Sundance Film Festival is not merely a vast improvement over the first, “The Other Side of the Bed.” It’s simply a superb, quietly devastating film in its own right.