Ambition and resourcefulness are of the essence in this zippy thriller from the Paraguayan filmmaking duo of Juan Carlos Maneglia and Tana Schémbori. The movie may lack the funds for elite-level production values, but it makes a vital and commanding bid for world-class status. That same dynamic is at play within the story itself, about a wheelbarrow-toting delivery boy (Celso Franco) in a labyrinthine street market, habitually transfixed by bootleg movies and spurred by dreams of stardom into transporting some criminally valuable cargo. He has help from a friend and romantic interest (Lali Gonzalez) whose assistance only makes things more complicated, and his main rival for the gig is a frantic father (Victor Sosa) who can’t afford medicine for a sick child and will do whatever it takes to obtain the needed funds. Also, the place crawls with thieves, and with cops who seem all the more menacing for being so easily bribable. Building on a simple, suspense-inducing setup, the filmmakers work well with the very basic ingredients of chase scenes, communication mix-ups, clever editing, and sly dark humor. Their milieu evokes Run Lola Run or Slumdog Millionaire, but the methods suggest what it might be like to see those movies stripped of their various pomposities. The real thrill of 7 Boxes is in how it turns an authentic sense of place, and an atmosphere of trickle-down desperation, into prime movie entertainment.