as Vorontsov

as Skvoreshnya

as Kartsev / Kartsev, senior lieutenant of state security

as Ivashev

as Gorelov, inzhener-mekhanik

as Druzhinin, assistant commander

as Arsen Davidovich Lordkipanidze, professor, ichthyologist

as Andrey Nikolaevich, professor, oceanologist

as Olga Ivanovna Bystrykh, doctor of the Pioneer submarine

as Ivan Nikolayevich Bystrykh, father of Olga Bystrykh

as Vasily Ivanovich Bazov, Colonel of State Security

as Sidorina, administrator of the Intourist hotel in Riga

as Pavlik, son of the captain of the ship "Arktika"