Dr. Fuentes is a medical doctor and professor nearing his retirement, and is concerned about leaving a legacy. He taught a group of seven - something he views as one of his greatest accomplishments - that trains young people to provide health care to impoverished citizens in the outlying hill country, where small agricultural communities struggle to survive.
Dr. Fuentes has recently heard rumors that his former students are lost, and possibly dead, so he musters up the courage and travels into the outlands to investigate, and meets Men with Guns.
According to Roger Ebert, it's not until he begins his journey that he discovers a world much different than the one he had imagined. The doctor's journey is enlarged by John Sayles into an allegory about all countries where men with guns control the daily lives of everyday people.
Some of the men are with the government, some are guerrillas, some are thieves, some are armed to protect themselves, and to the ordinary people it hardly matters: The man with the gun does what he wants, and his reasons are irrelevant--unknown perhaps even to himself.
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