Dentist Lauri Liesi is performing as a magician in the Hotel Metropol. Meanwhile, during his performance top-secret letters of engineer Arpila are stolen from his room. Mr. Liesi is then being accused of the theft. To clear his name he starts to investigate and search the culprits from the criminal underworld. With the help of a former circus man Romonen he begins to unveil the truth.
| Actor | Role |
|---|---|
 Joel RinneLauri Liesi | Lauri Liesi |
 Hilkka HelinäRaija Arpia | Raija Arpia |
 Ritva ArveloKirsti Salme | Kirsti Salme |
 Eine LaineMrs. Luokki | Mrs. Luokki |
 Rauha RentolaMilla | Milla |
 Reino ValkamaPerttu Romonen | Perttu Romonen |
 Tauno MajuriReino Arpia | Reino Arpia |
 Paavo JännesNiklas Rami | Niklas Rami |
| KKaarlo AavajokiRomsu | Romsu |
 Matti AulosAnders Luokki | Anders Luokki |
 Kaarlo HalttunenDoctor (uncredited) | Doctor (uncredited) |
| PPaavo HonkamäkiMattinen (uncredited) | Mattinen (uncredited) |
| VVeikko HuuskonenWaiter (uncredited) | Waiter (uncredited) |
| EEero KilpiHacklund (uncredited) | Hacklund (uncredited) |
 Emma VäänänenAlma (uncredited) | Alma (uncredited) |