About the title
The contents of the wonderful Doctor's yellow suitcase cure not only colds and flu, but also sadness, loneliness, cowardice, and shyness. Petya is a modern-day recluse of a boy who can't be coaxed outside — he's afraid of people and other kids. His parents decide to turn to the wonderful Doctor, but his magic suitcase is stolen. From this moment a series of adventures begins. In the end, Petya not only helps the Doctor, but also finds loyal friends and gets rid of his "ailment."