A six-foot tall cat in a red and white striped hat shows up in a house where a young boy and girl live, and shows them "fun" tricks, which actually turns out to look bad then worse when he unleashed two Things from a box.
- "I know it is wet, and the sun is not sunny, but we can have lots of good fun that is funny!"
- "Your mother will not mind at all if I do!"
- "He should not be here when your mother is out!"
- "I call this game 'Fun-in-a-Box!'"
Spanish Language Edition
On April 12, 1967, this book was released in both English and Spanish. It was translated by Carlos Rivera. Because the translation was literal and a lot of the Seuss-y rhyming was lost, many readers actually hated this book.
Audio Cassette Edition
There was an audio cassette edition of this book, released on October 12, 1987.
40th Anniversary Edition
All 1997 prints of this book were seen in stores as "Special Anniversary Editions". The interior of the book saw no changes whatsoever.