For several hundred years there's been a near mythical story in Buenaventura - about a large treasure of gold that can be found in the so-called ""lost city"". Eva Bergeron, a beautiful German archeologist, has an old map and hires Rio to help her look for the treasure. However, Carlos Rey De Lupos, the Minister of Antiquities, wants the map for himself and kidnaps Eva. Rio prepares to rescue Eva but finds out that she hasn't been completely honest: she's no archeologist...

Lucie Ortega, a beautiful nightclub singer at the Club Saludos, contacts Rio for help. She needs to leave Buenaventura immediately to be with her sick mother in the Andes but cannot leave unless her boss at the club pays her the 75 million Pesos he owes her. Rio - not knowing that Lucie has been sent to him by the always unreliable Furman - naturally agrees to help an attractive damsell in distress, and goes to the Club Saludos and gets the money from Lucie's boss, Mesarigos. Shortly afterwards, Mesarigos is found murdered, and Lucie and the money have vanished. Rio, who was Mesarigos' last visitor, gets charged with murder.