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.
as Foma Konovalov
as Glafira
as Pasha Zhgutov
as Valya
as Danya
as Grandson Foma Konovalov
as Stepan Novoselov
as Natalya Yevgeniyevna
as Skornyakov
as Foreign Ship Captain
as Marya Stepanovna
as Pyotr Mikhaylovich
as Foreign Ship Skipper
as Radio Operator
