The actor who moved mountains with the word “what”—Remember in Pulp Fiction: “Say ‘what’ again, I dare you”—has lent his voice to a children’s book.

Not just any children’s book, but The New York Times bestselling book “Go the F*** to Sleep,” by Adam Mansbach. The book, targeted to weary parents, is a spoof of the rhythmic, soothing, good-night children’s genre. It debuted this week as No. 1 on the Times bestsellers list among—get this—“advice” books. It was also the top-ranked book on Amazon, before it even hit bookshelves.

“Go the F*** to Sleep” started as a Facebook joke. Mansbach wrote on his Facebook wall last June: “Look out for my forthcoming children’s book, Go the F**k to Sleep.” He was joking at the time, but eventually penned the book and sold a publisher on the idea.

It gained traction after the book was leaked and went viral. Last month, a representative from the publisher said it had done “nothing” to promote it.

Seems like the publicity machine is gearing up now. This week, news spread that Jackson had recorded an audio version of the book—which you can download for free here—and that director Wernor Herzog is also planning an audio edition.

On Thursday night, Jackson stopped by "The Late Show With David Letterman" to plug the book and offer a quick reading. This video is safe for work.