It was confirmed in July that Guillermo Del Toro would be adapting H. P. Lovecraft’s horror novel At the Mountains of Madness with James Cameron acting as executive producer.

Collider are now reporting that Universal and Del Toro may be at deadlocks over who they want to cast in the lead role. Universal appear to want James McAvoy, while Del Toro wants to cast Tom Cruise, whom he met earlier this year to discuss a new Van Helsing project.

At the Mountains of Madness will be shot in 3D, with filming likely to begin in May 2011, meaning both McAvoy and Cruise would be available, so it’s now up to Universal and Del Toro to reach an amicable agreement.

HP Lovecraft’s At the Mountains of Madness was a horror novella, originally serialised in 1936 and included within several issues of Astounding Stories magazine.

The plot is detailed below:

A 1930s geologic expedition ventures into the unknown wastes of Antarctica. There part of the expedition suffers a horrendous fate. The survivors set out to discover what happened and find a vast city buried in the ice which pre-dates mankind. As they explore the fantastical ruins the scholars discover that the city’s terrifying builder’s may still be there.

Who would you like to see play the lead role – McAvoy, Cruise, or someone completely different? Have your say in the comments section below.