Knock, knock. Who's there? The Amazing Book of Knock Knock Jokes. The Amazing Book of Knock Knock Jokes who? The Amazing Ummm... let's start again. This book, The Amazing Book of Knock Knock Jokes, contains one hundred and fifty hilarious jokes for kids of all ages, as well as a short section on the history of the joke style that will probably interest your parents (but it's OK, you can skip over that bit). The author believes that every single one of these jokes will make your head fall off with laughter and your sides split with mirth, so highly recommends exercising caution. Although wouldn't it be great if your head really DID fall off?! Let's find out...