Leonardo Books in Order

The Leonardo story begins with a problem that’s funny on the surface and surprisingly relatable underneath: Leonardo wants to be a terrible monster, but he just isn’t very good at it. The other monsters have signature scares. Leonardo has effort and ambition, and not much else.

So he does what a determined kid would do, he researches. Leonardo studies what scares children and makes a plan to find the perfect target. The book plays those “monster rules” for laughs, with Leonardo treating fear like a skill you can learn if you just try hard enough.

Then he meets a boy named Sam. Sam doesn’t look especially scared of monsters, which makes Leonardo even more determined to prove himself. Leonardo commits to one big scare, and for a moment he finally feels like he’s succeeded.

Then Leonardo gets what he wanted, and it doesn’t feel the way he expected.

Instead of leaning into the usual “monster wins” ending, the story pivots into empathy and friendship. Leonardo has to sit with the fact that being good at something isn’t always the same as being proud of it. And Sam, who turns out to have his own needs and his own kind of loneliness, becomes more than just a target.

The tension stays gentle, but the emotional question is real: what do you do when you realize you’ve hurt someone? The book doesn’t hand out a lecture. It lets Leonardo make choices, and it shows how a bad moment can turn into a better one when someone is willing to admit they messed up.

Willems’s art keeps everything clear and readable. The characters are expressive, the backgrounds stay simple, and the pacing moves quickly, which makes it a great read-aloud for preschool and early elementary kids. There’s plenty of humor for monster fans, but nothing is too scary or graphic. The joke is always in the characters, not in making the reader feel unsafe.

Even though this page is labeled as a series, Leonardo, the Terrible Monster works perfectly as a standalone. It’s one of those books families return to when they want something short, funny, and warm, with a message that shows up naturally in the plot instead of being printed on top of it.

If you’re reading around in Mo Willems’s world, Leonardo also fits with his bigger themes: wanting to belong, testing out an identity, and learning that connection matters more than “winning.”