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WARNING: READ BEFORE PLAYING! (Really, at least what's underlined)

This game is under copyright Jackbox Games. It was released in 1995 on PC and Mac (more about this on Wikipedia), and I wanted to make a playable version in a browser by extracting art and sound content and by rewriting (and by that I mean simulating) the engine in JavaScript.

I have no connection with Jackbox Games, and this version of the game is not an official development. It's purely a fan work, totally non-profit, and will always be free-to-play and ad-free. The only UK version out there is more than 15 years old, and I just want to make people discover this game and make other people nostalgic (and have fun developing it too).

This is only a sample of the full game, and there's a lot missing. Many things just don't work yet. I'm trying to add new content from time to time. Recently, it's been made possible to play the full version online!

The game works better in Firefox and Chrome. It's possible to play in "full screen", by clicking on the top link and hitting F11 (F11 and Escape to get back to normal). Internet Explorer doesn't allow CSS3 fonts and doesn't handle sounds very well. Smartphone browsers don't either, apart maybe for Chrome for Android, which just barely works.

The goal of this project is to convert the whole game and to make it a multiplayer online game. I don't have much free time, so it's not going to be soon, but we'll see! This is part of a bigger project. You can check out the website You Don't Know JavaScript, the Facebook page ydkjs and the Twitter account @ydkj_eu for the latest news. And if you don't know the game already, go ahead and give it a try!

Contact :
Version française disponible!
German version available! Try it:

YOU DON’T KNOW JACK® Jackbox Games, Berkeley Systems, Jellyvision, Melog Productions Inc, BMG Interactive, Take-Two Interactive