It'd be easy to assume that, with the success of Guardians of the Galaxy, Marvel can do no wrong. Even so, comic book film adaptations are already starting to dominate the release calendar, even four years in advance. Marvel's Inhumans movie is not only an incredibly obscure comic book (not unlike Guardians), but it could be released at a time where movie-goers are simply sick and tired of comic book blockbusters.

There's a good chance that the success of the Inhumans movie will come down to its cast, same as Guardians of the Galaxy. Unfortunately for fans, there's no telling who will star in the Inhumans film, especially not this early in development. The film won't be released until 2018; it'd be crazy to release a cast list now.

Or not: despite the fact that Inhumans is still years away from entering production, Marvel may have already announced one of the film's major players:

Looks like Vin Diesel wasn't content to play just one role in the Marvel Universe, as the man who brought Groot to life in Guardians of the Galaxy will likely be appearing in the Inhumans film as well.

It's about as subtle as Marvel can get these days. Even without the Inhumans t-shirt, it's clear to see that the text behind Diesel says 'Inhumans' as well. It's like the folks over at marketing were too coy to just spell it out (hence Diesel blocking out the word 'Inhumans' in the background), but were then concerned that people wouldn't get it and Photoshopped the word onto his shirt.

For those who don't follow incredibly obscure comic books, the Inhumans are a race of superhuman beings that band together in order to fight off one of the Marvel Universe's biggest alien threats. There's the leader, the girl, the big muscle-bound one, the freaky alien-looking one, and the dog: if that doesn't sound a little bit like Guardians of the Galaxy, it's probably time to go and re-watch the movie.

In all fairness, there's no telling that Inhumans will be anything like Guardians of the Galaxy...but Vin Diesel appearing in both adaptations could certainly make the movies feel similar. What's strange is that Diesel already has a new cover photo on Facebook: while the Inhumans photo still exists, a photo of Diesel and his dog has since taken its place.

Perhaps the post was a bit premature? Until Marvel itself makes a statement, there's no way to tell if Diesel is in fact slated for the Inhumans film...only time will tell, as they say.