You had to know this was coming. There's a bidding war heating up between Hollywood studios over the rights to bring Glenn Greenwald's forthcoming tell-all book about the Edward Snowden affair to the big screen. 

Greenwald's book, set for a March 2014 release from publisher Metropolitan Books, promises to be the definitive account of how a former NSA contractor, Edward Snowden, was able to leak damaging details of the secret spy agency's surveillance practices. So it's not all that surprising that 20th Century Fox, Sony Pictures Entertainment and HBO were all jockeying for the movie rights, according to The New York Times' Michael Ceiply. (This is likely a different project than the Snowden movie shopped by the William Morris Endeavor this summer.)  Nothing is signed and delivered yet, but the official Greenwald-Snowden movie is coming. 

At least one studio has already pulled out of the bidding because of the myriad legal and logistical issues that plague the telling of Greenwald's Snowden story. The ending, really, is the project's biggest issue. Snowden is holed up in Russia, dodging extradition from the U.S. You'll remember that his stay is supposed to be a temporary one. We don't know what happens next, so neither does the studio, and that could have a huge effect on the movie's historical significance. Zero Dark Thirty wasn't made until years after Osama bin Laden was killed. That story had a beginning, middle and end before it was made into a movie. Snowden's is still in its second act. 

That's what made Fox back out of negotiations. But there are other legal complications that studios need to watch for, as Cieply explains

Further complexities involved the structure of any proposed deal. Mr. Greenwald is selling the rights to his book and may include his own life rights. But his journalistic collaborator, Laura Poitras, and Mr. Snowden have not put their own life rights for sale, according to the people briefed on the film. That leaves potential buyers to rely on legal precepts of fair use in portraying them, or on their assurances that they will not seek to interfere with a movie.

Speaking of Zero Dark, the eventual Snowden movie will also anger politicians in much the same way the Bin Laden movie did. Backlash from lawmakers over the movie's accuracy (in particular its portrayal of the CIA's interrogation practices) arguably cost the movie in the Oscar race. Zero Dark was let off the hook eventually, but not until after award season passed, and Zero Dark went home mostly empty handed on Oscar night. And this was over a movie about American troops killing Osama Bin Laden. The potential backlash for a Snowden movie would likely be much, much greater.