Riddle of the Letter from the Past

When was the last time you looked through your family album? The story of young Sonya will tell you how important it is to remember your ancestors, to not hold grudges, and to understand in time what is truly important in life. A whole detective story has unfolded around an ordinary family, and its investigation was taken up by Sonya and Trofim, her classmates, along with their loyal companion — the dog Sherlock. The ball of family secrets will surely be unraveled!