Reader question - Can I re-adapt something that's in the public domain?

I got an email from Tim entitled "Writing for Existing Properties, Sort of."

Trust me, I know. I know I can't write the next Pirates of the Caribbean to get in on all that cash, or Transformers, or even Die Hard 5: Live Free or Die Harderer.

My question is about King Kong. I, of course, have a brilliant idea for a King Kong sequel/reboot/reimagning/prequel. I thought that based on the 2005 Peter Jackson version the copyright was owned, however according to the ever-reliable wikipedia:

"MCA/Universal attempted to sue Nintendo for copyright infringement in Universal City Studios, Inc. v. Nintendo Co., Ltd., claiming that the game infringed its copyright for the film. However, they lost and had to pay Nintendo $1.8 million in damages when it was discovered that King Kong was in fact in the public domain at that time and that MCA/Universal knew this when they filed the lawsuit. They did not own the copyright to King Kong and had not trademarked the name "King Kong". They had even argued in the past that the name "King Kong" was in the public domain in Universal City Studios, Inc. v. RKO General Inc., et al."

So here's my question: can a property be deemed "in the public doman" still be property of a studio? I understand that Universal owns the 2005 version and all the likenesses, blah blah blah, but does that preclude me from writing ANOTHER King Kong movie based on the above ruling?

As Scott Myers always says in a prelude to answers of this nature, "I'm not a lawyer. I don't play one on TV." Bear that in mind as I answer.

As I understand it, if something is in the public domain, nothing should preclude you from writing your own version of it - so long as your adaptation sources only the original material. As an example of this, I recall the creators of Cruel Intentions noting on the DVD commentary track noting how careful they had to be during their rewrites. Cruel Intentions was an updating and adaptation of the novel Les Liaisons dangereuses, which had previously been adapted as Dangerous Liasons. (Les Liaisons dangereuses was in the public domain, while Dangerous Liasons was not.)

I ran across this a few years back when I wrote a spec script that was a sequel to The Wizard of Oz. My notion was that it would be a sequel to the books rather than the 1939 film - a conceit that I felt not only offered more interesting story paths, but also precluded the need to secure the rights to MGM's classic film. After all, the original novel is in the public domain - which is also why you see so many Oz properties floating around out there.

[Side note - when I queried with this, I was a little dismayed at how many agents were ignorant of the fact Oz was in the public domain. This was especially surprising since it was my bad luck to start pushing this script just as a wave of Oz projects was making its way through Hollywood, effectively killing the market for my take.]

So my advice is to research the source material thoroughly and make note of precisely what's in the public domain and what might still be under copyright laws.