Did you know a third-person shooter Warhammer 40K game was under development? Well, you shouldn't because it hasn't even been announced yet. However, someone has leaked a developer walkthrough video of Warhammer 40K: Space Marine to the Internet and it shows off nine minutes worth of gameplay footage.

Now now, I know what you're saying: "It's about time someone made a game about space marines! What a completely unexplored concept by console shooters!" This game doesn't look too shabby, though. The video shows a marine in enormous power armor running through a very palatial building and tearing apart gun-wielding goons with an assault rifle and a big ass sword. We also get to see some very bloody execution animations, complete with cinematic camera work. None of it is mind-blowing but to be fair, this is likely a very early build of the game. If this turns out to be a hoax, it's certainly a well-made one.

THQ has the video game rights to the Warhammer 40K series so I imagine we'll hear something from them soon if this is legit. According to the YouTube posting, the game is in development for PS3 and Xbox 360.