Sarmo explores the mystery associated with the murder of a landowner and the tangle of crimes, threats, and conspiracies created by a letter he left behind. At the same time Sarmo helps the consuls of imaginary small states of South America in a difficult situation, and charms their daughters.
| Actor | Role |
|---|---|
 Joel RinneRainer Sarmo | Rainer Sarmo |
 Hilkka HelinäKirsti Ström | Kirsti Ström |
 Reino ValkamaMikko Vehmer | Mikko Vehmer |
 Mai-Brit HeljoIrma Porri | Irma Porri |
 Paavo JännesLauri Porri | Lauri Porri |
 Jalmari RinneVeikko Viira | Veikko Viira |
 Aarne LaineKaarlo Luode | Kaarlo Luode |
 Siiri AngerkoskiIda Holopainen | Ida Holopainen |
 Arvo LehesmaaOskari Karlio | Oskari Karlio |
 Thure BahneHerbert Hertzog | Herbert Hertzog |
| JJorma NortimoDon José Gonzales | Don José Gonzales |
 Ekke HämäläinenTimo Muura | Timo Muura |
 Kauko VuorensolaReikko | Reikko |
 Uuno MontonenPorter | Porter |
 Matti LehteläHyrkki | Hyrkki |
| UUrho KastariRudi | Rudi |
| VVappu JurkkaEllen (uncredited) | Ellen (uncredited) |
| SSointu KouvoHilma (uncredited) | Hilma (uncredited) |
| AAino LehtimäkiMiina (uncredited) | Miina (uncredited) |
| EEino RitariHärkönen (uncredited) | Härkönen (uncredited) |
 Pentti IrjalaPorter (uncredited) | Porter (uncredited) |
| IInkeri Aalto(uncredited) | (uncredited) |
| LLahja Vilén(uncredited) | (uncredited) |