Every day, ten-year-old Sasha looks outside her window to the rail tracks that lead away to a new life. Thousands of questions about the world pop up like mushrooms in her mind. Grown-ups don’t have much patience for explanations, except her father; he calls her Kernel and she calls him Sesame. He is a doctor and he doesn’t make distinctions between poor and rich patients, nor between Russian or Jewish, Christians or others. These are the principles that Sasha grows up with in pre-revolution Russia, fighting against injustice and learning what it means to be a true hero. With the anticipation and enthusiasm that only children can master, she awaits the great change that will knock on their doors.