Maruko gets a letter from Fujiki-kun. Thinking it might be something exciting—perhaps even a love letter—she opens it eagerly, only to find a chain letter promising disaster. Unless she sends the same letter to four more people within three days, it says, misfortune will strike. Seeing how frightened she is, Dad tears the letter to pieces and assures her that nothing of the sort will happen.
まる子に藤木クンから手紙が届く。ラブレターか何かと期待して封を開けると中には不幸の手紙が入っていた。三日以内に同じ内容の手紙を四人に出さないと不幸が訪れるらしい。おびえるまる子を見かねたお父さんはその手紙を破り捨てて何も有りはしないと言い聞かせる。