The enemy agents from an unknown nation have secret automated facilities set up in the Atlantic and Pacific oceans for the purposes of sinking ships. The super submarine "Pioneer" and it's intrepid crew is dispatched to find the source of these mysterious sinking's...Unknown to the captain, his chief engineer is working for the bad guys, intent on stopping their efforts, at any cost...It seems the real chief had a twin brother who was a circus acrobat who murdered and replaced him.
as Vorontsov
as Skvoreshnya
as Kartsev
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 Kartsev, senior lieutenant of state security
as Sidorina, administrator of the Intourist hotel in Riga
as Pavlik, son of the captain of the ship "Arktika"
