Yurka is a self—contained twelve-year-old schoolboy who is grieving the loss of his father. The ordinary course of his life changes when new students appear in the classroom — a brother and a sister. Together they will have to grow up and find out what true friendship is worth.

The boy Igor receives a dog as a gift for his birthday and runs away from home with it. But now the two of them must save Igor's father, an astronaut, from death.