I don't think I've read that tale - is it in the Silmarillion? I only got a couple of chapters in before giving up.
I'm guessing they're either going to expand on little bits of backstory (eg. the stuff about the wizards kicking the Necromancer out of Mirkwood) or they're going to make up something completely new that isn't supported by the original text at all. I wouldn't be surprised if it was the latter. I have seen a rumour that it will concern Aragorn's younger days but there may be nothing to that.
New York Times says "The untitled sequel is described as bridging the 60-year gap between the end of J. R. R. Tolkien’s "Hobbit" and the beginning of the “Rings” trilogy."
As I understand the story not all that much happened during that period. Bilbo pottered around in the Shire working on his book while Sauron quietly rebuilt his strength down in Mordor. There are a few pieces of backstory that could be expanded upon, such as how Saruman gradually fell under the spell of Sauron and the one ring, what happened to the dwarves who went to Moria to look for the dwarven rings of power, and Gollum's trip to Mordor, but I'm not convinced there's a single consistent plot there that you could hang a movie on.
I wonder if PJ has been Really Smart, and has pitched the Tale of Luthien as 'the Hobbit, part 2'???
I'm guessing they're either going to expand on little bits of backstory (eg. the stuff about the wizards kicking the Necromancer out of Mirkwood) or they're going to make up something completely new that isn't supported by the original text at all. I wouldn't be surprised if it was the latter. I have seen a rumour that it will concern Aragorn's younger days but there may be nothing to that.
of course, when they do die, the papers will print their Hobbituaries.
"The untitled sequel is described as bridging the 60-year gap between the end of J. R. R. Tolkien’s "Hobbit" and the beginning of the “Rings” trilogy."