Belgian bibliophiles have joined in a nationwide scavenger hunt for books, inspired by the popular smartphone game Pokémon Go. Reuters reports that Belgian schoolteacher Aveline Gregoire came up with the game, called Chasseurs de Livres (“Book hunters"), after playing Pokémon Go with her kids.

The game, which is played through Facebook, has garnered more than 40,000 players in just a few weeks. Players throughout the country hide books and leave clever clues for one another on the Chasseurs de Livres Facebook page. When players successfully find a book, they read it, then release it back into the wild. There are no rules about what kinds of books can be hidden, and selections range from kid’s books to Stephen King novels.

Gregoire tells Reuters that she initially launched the game, in part, because she had too many books cluttering her library. She just wanted to find a good home for the books she no longer had space for. But the game took off rapidly and unexpectedly, and Gregoire is now contemplating creating a more professional phone app to accommodate its players.

While Chasseurs de Livres lets players collectively hunt down hidden treasures, just like Pokémon Go, it also serves as an informal nation-wide book club. On the game’s Facebook page, Gregoire encourages players to not only leave clues for one another, but to share their thoughts and feelings about the works they’ve read.

[h/t Reuters]