Twenty-five to thirty thousand Jews were issued life-saving certificates of Salvadoran citizenship thanks to the El Salvador Action and its officials: Consul General Jose Arturo Castellanos and his first Secretary, George Mandel-Mantello. This is the story of how one of the world's smallest countries facilitated one of the most successful rescue operations of World War II. In 1938 Colonel Castellanos was assigned to Hamburg to open the consulate of El Salvador, then was sent to Switzerland. In 1942, as Europe was under siege by the Nazis, a wealthy Romanian Jew named George Mandel, who had befriended Castellanos, asked for his help. So Castellanos appointed him First Secretary of El Salvador's consulate in Geneva. When Mandel received his Salvadoran passport, he added "Mantello" to his name in order to sound more Latin. Soon afterward, inspired by the rescue efforts of his contemporaries and driven by the spreading horror of the genocide surrounding him, Mandel-Mantello suggested that they issue Salvadoran passports as rescue tools. Castellanos declined, citing the increased scrutiny of foreign passports, because spies commonly forged them. He instead suggested certificates of Salvadoran citizenship, and thus began one of the greatest humanitarian efforts in the history of the Holocaust. Glass House was filmed over a three year period on location in Central America, Switzerland, Hungary and Spain by the director and his wife Leonor, who is herself a native of El Salvador. The inspiring story of the El Salvador Action, and the Glass House (one of the protected buildings from which Salvadoran citizenship certificates were issued), is told by the sons and daughters of the heroes themselves, as well as survivors who owe their lives to the tiny country with a brave and humble heart.