Supply clerk Chuvilikhin goes to Moscow to fulfill his coworkers' errands. In the hustle and bustle of the capital, he loses the list where the name of the sheet music to be bought for the director's wife was written down. Anatoly Stepanovich rushes around the city trying to remember the melody.

A mushroom offers the animals of the forest, an ant, a butterfly and a mouse shelter from the storm. A little rabbit, who wants to hide from the fox, also finds a place with him. The mushroom grows, stretches and stretches as it sees the good will of the other animals to help the hare.