Remember the name Catalina Sandino Moreno. The heartfelt and harrowing performance she gives here should put her in line for a heap of year-end awards. Moreno plays Maria Alvarez, a seventeen-year-old Colombian girl who can’t alleviate her family’s poverty with the pittance she earns slaving in a flower factory. Maria sees an out with an offer to become a mule — she can join other Colombian girls who smuggle drugs into the United States. Debuting director Joshua Marston, who also wrote the taut screenplay, shows Maria being taught to swallow drugs wrapped in packets — she sips soup to make them go down without gagging. If the drugs in her belly should seep out during Maria’s turbulent jet flight to New York, she could be poisoned or arrested or both. Marston builds incredible tension. But it’s the human drama etched on Moreno’s young, weary face that gives Maria its potent punch.