Appointment in Honduras

Aboard a tramp steamer navigating Central America, Mr. and Mrs. Sheppard find themselves alongside five prisoners headed for a Nicaraguan prison, and Corbett, an American transporting funds for a Honduran counter-revolution. When denied entry into Honduras, Corbett frees the inmates, and together they seize control of the vessel. They take the affluent Sheppards hostage and embark on a treacherous journey upriver to meet Corbett's contact, facing numerous dangers lurking in the jungle along the way.