Three boys are helping Soviet Intelligence to catch German spies during WWII.

Vladimir Lelyotkoas Styopka Panfilov
Pavel Luspekayevas Ivan Vasilyevich, KGB major
Oleg Belovas Aleksey Burakov
Aleksandr Mikhaylovas Uncle Petya / German spy
Fyodor Odinokovas Semyon, truck driver
Aristarkh Livanovas Zhora "Brunette"
Andrey Krupeninas Shurka "Krendel"
Aleksandr Lipovas Valeriy Kaplunov, rocketeer