In July, we reported the exciting news that Guillermo del Toro would finally be making his long-in-development passion project At the Mountains of Madness with James Cameron producing and in 3D. Sources have now told us that Universal wants James McAvoy to play the lead in the film, but del Toro wants Tom Cruise to star. Chris Pine’s name was also being tossed around, but his busy schedule may be too packed.

We know that Cruise and del Toro probably met before when discussing the possibility of a new take on Van Helsing with Cruise to star and del Toro producing. That didn’t work out, but del Toro must have left with a positive impression of the actor. Hit the jump for a synopsis of At the Mountains of Madness and for a refresher on what both Cruise and McAvoy have on their plates.

Here’s a brief synopsis of Lovecraft’s novella:

The story is written in first-person perspective by the geologist William Dyer, a professor from Miskatonic University. He writes to disclose hitherto unknown and closely kept secrets in the hope that he can deter a planned and much publicized scientific expedition to Antarctica. On a previous expedition there, a party of scholars from Miskatonic University, led by Dyer, discovered fantastic and horrific ruins and a dangerous secret beyond a range of mountains taller than the Himalayas. [Wikipedia]

When Steve spoke to del Toro at the Saturn Awards in June, the award-winning director said it was unlikely that At the Mountains of Madness would be his next project due to various factors. Thankfully, those obstacles were overcome and production on the film (which will be shot in 3D) is set to begin in May 2011.

McAvoy is about to start filming on Matthew Vaughn’s X-Men: First Class where he’ll play the young Professor Charles Xavier (aka Professor X). He’s also attached to co-star in Tom Tykwer’s adaptation of David Mitchell’s novel Cloud Atlas.

As for Cruise, he starts shooting on the fourth Mission: Impossible in October. He’s also planning to star in a Tropic Thunder-spinoff movie about uber-mogul Les Grossman.

With filming not scheduled to begin for almost a year, there’s plenty of time to get casting sorted out. While it’s not unusual for actors to attach and detach from projects, McAvoy and Cruise are the names we’re hearing connected to At the Mountains of Madness at this time.