And Branagh seems to be making all the right moves. He's avoided reported studio pressure to cast a famous face - Josh Hartnett was said to be in the running - and instead plumped for the little-known Chris Hemsworth, who was Captain Kirk's dad in Star Trek for about five minutes. As everyone who saw Daredevil knows, superheroes should not be played by well-known actors; it's harder to suspend your disbelief when the spandex-sporting great lump on screen is someone you can catch in the tabloid gossip columns on a daily basis.

This week alone, Branagh has also reportedly added Idris Elba and Kat Dennings to his cast list. Elba is said to be playing Heimdall, a guardian who stands to defend the Norse heaven, Asgard, from intruders, while Dennings will play a work colleague of the previously-cast Natalie Portman, a possible romantic interest for Thor, Jane Foster.

It seems likely both roles will be small ones, which is a pity. Elba is long overdue a chance to show the talent he exhibited on the small screen (Obsessed really doesn't count), while Dennings deserves a part where she's not required to act as the foil for a showier co-star. Neither will get what they need this time around. Larger roles will go to reliable rent-a-Brit Anthony Hopkins and Branagh favourite Tom Hiddleston, a RADA-trained English actor who's nabbed the role of villain Loki.

Thor, which starts shooting next year for a 20 May 2011 release date, seems likely to stay close to the comic book tale of the Norse god of thunder, created by Stan Lee in 1962 as a new kind of hero. The Marvel legend wasn't sure how to top the formidable superpowers he'd handed to the Hulk, until he came up with the idea of making his next character a real live deity.

In the comics, Thor is an arrogant warrior whose reckless actions in Asgard reignite an ancient war. As punishment, he's cast down to Earth and forced to live among humans. In the film, he will learn what it takes to be a true hero when his brother Loki sends the darkest forces of Asgard to invade Earth.

Some reports have suggested Thor will maintain his human alter ego from the comics, a partially disabled medical student who is initially unaware of his godly persona. But Ain't It Cool News reports that the character, Donald Blake, will not be in the film at all. It's all very confusing, since Blake and Foster were lovers in the comics: how will Portman's character fit into things if he's not around?

But that's a conundrum which looks like a piece of cake compared to the poser Warner Bros creatives will have to negotiate if they want to bring another Superman film to the big screen without spending a small fortune on buying back the rights.

Industry blogger Anne Thompson says there is nothing doing on the Man of Steel due to a recent legal ruling which handed a measure of control over future big screen outings to the heirs of Superman creator Jerome Siegel.

Warner had been leaning towards the idea of a total reboot for the series, following the relatively poor showing of Bryan Singer's insipid sequel in 2006. Due to the ruling, that prospect is pretty much dead in the water, as the studio now no longer owns the rights to the origins story of the character as first published in Detective Comics's Action Comics, and later transferred to the big screen. To top that, in 2013 the Siegel estate will regain full rights to the character, meaning it could sell off Superman to another studio. Although given the mess Warner has made, that might not be the worst thing in the world.