The knock-knock joke: a kid classic. So many funny, punny punchlines. It was just screaming for its own book. To do this classic joke justice, we decided to gather fourteen of the best-known and most talented children's book artists to illustrate their favorite punchlines. The results are wacky, zany, and absolutely hilarious.

If you knock on Tomie dePaola's door, beware! Is that a girl or a gorilla? Who's knocking at Saxton Freymann's door? Just a couple of talking lettuces. Talking lettuces?! One impatient cow can hardly wait to get through Laurie Keller's door, and David Small has a surprise waiting for his intruding vampire.

In this collection, you?ll recognize some of your favorite jokes and be surprised by new ones. But one thing is certain: Each time there's a knock, you?ll want to answer the door!