It's been heavily speculated for the past couple of months that Christopher Nolan's return to Gotham City for a third time would see the Dark Knight fighting The Riddler. And thanks to a bit of work over at FirstShowing, it now seems much more likely that that's the case.

Nolan's Batman 3 (as it's becoming known) is set to shoot early next year, and as is the case with all of the director's movies, he's been keeping things close to his chest. That hasn't stopped rampant speculation regarding who the villain is, but now a source has told FirstShowing that, in this case, the collective might of the Internet might have called this one correctly.

The site's source has reportedly got hold of a studio casting grid that specifically lists The Riddler in the character list for Batman 3. Furthermore, the site notes that there's a name next to that of the character: Mr Joseph Gordon-Levitt, currently being seen in Nolan's Inception.

That's not to say that Joseph Gordon-Levitt has signed on the dotted line, of course, although his status on the casting grid is listed as "interested". That's a very different beast to ‘signed on the dotted line and committed much of the next year of his life to the role'.

The grid apparently lists the age range for the character as 35-45, too, which doesn't fit Gordon-Levitt particularly, given that the actor is currently 29. But we suspect that there might be some flexibility there.

This is still all yet to be confirmed, and could, of course, change at any time. But it's the first step towards substantive confirmation that The Riddler is the man that Bruce Wayne needs to be worried about in July 2012.

Also, we'd wager that Nolan will put a second, supporting villain in there too. But again, that's just speculation on our part.

Here's the story at FirstShowing.