Is Vin Diesel Secretly Playing Thanos In Guardians Of The Galaxy?

We always love a good conspiracy theory, and MTV News is pushing a pretty outrageous one. MTV is speculating that Vin Diesel isn't actually playing Groot in Guardians Of The Galaxy. They think all the Groot talk is just a cover up for Vin Diesel's real role as Thanos. Over the last several months, Vin Diesel has been posting to Facebook, uploading videos, and pretty much telling anyone that will listen that he's playing Groot in Guardians Of The Galaxy. However, Marvel Studios has yet to issue an official press release announcing him as Groot, as they have done recently with other big name actors who have been cast in their films. The lack of any official announcement is something we've wondered about as well, and MTV's theory probably makes as much sense as any other reason that Marvel Studios hasn't officially announced Vin Diesel's casting. It's also interesting that Marvel Studios hasn't officially announced who is playing Thanos in Guardians Of The Galaxy yet. The one big glitch in the theory is that Vin Diesel has been busy working on Fast & Furious 7, and Guardians Of The Galaxy just finished shooting. With Groot, Vin Diesel could add his voice work later. But with Thanos, most would assume that an actor would need to be there to play that character. However, it's not out of the realm of possibility that Thanos could be a CGI character this time around. Or maybe Thanos' role isn't that large in Guardians Of The Galaxy, since Ronan The Accuser has been said to be the main villain. If MTV's theory is correct and Vin Diesel is playing Thanos, then it could also explain Vin Diesel's references to another Marvel Studios movie down the line. Maybe, Thanos plays a fairly minor role in Guardians Of The Galaxy, but he's being set up as the main villain for Avengers 3.