Brother and sister Danya and Valya move with their mother to a northern seaside town and immediately become participants in an exciting but dangerous adventure.
Foma Konovalov
Glafira
Pasha Zhgutov
Valya
Danya
Grandson Foma Konovalov
Stepan Novoselov
Natalya Yevgeniyevna
Skornyakov
Foreign Ship Captain
Marya Stepanovna
Pyotr Mikhaylovich
Foreign Ship Skipper
Radio Operator
