Favreau initially had his Iron Man buddy Robert Downey Jr. pencilled in for the C&A lead, but scheduling conflicts have kept RDJ out of this one: he's busy prepping a Sherlock Holmes sequel and maybe fitting in Oz, The Great and Powerful with Sam Raimi.

Stepping into the spurred boots will be Daniel Craig, who has a bit of spare time on his hands, what with all the legal wrangling that is keeping the next Bond movie from getting out of the stables.

Craig's appointment was an interesting turn, though. He should be able to pull off the grizzled, craggy, tough-guy role in his sleep, and his recent stint on Broadway showed he could handle an American accent (and dodgy 'tache) if required.

Putting Craig in the lead role shakes things up somewhat: he should hopefully ground the story in a way that Downey Jr. and his brash charms may not have done.

Roberto Orci says of the developments: "We started the movie and the first draft was very kind of jokey and broad and then it went very serious. You kind of swing back and forth between the two extremes and the tone until you find the exact right point where a Western and a sci-fi movie can really shake hands without it seeming unnatural."