Deadwood, one of the best TV series in history, disappeared without a proper ending in 2006. After 3 seasons, it wasn't even canceled by HBO... they just suddenly opted not to pick up the options for the cast. They promised a movie to finish up the story... but it never happened.
If you have not seen Deadwood, I strongly recommend you watch all 3 seasons. If you fail to heed my recommendation, and forge ahead with watching this movie... be warned that this show has more curse words in a single hour than you will probably hear in a normal year. I will miss Powers Booth, he was a key player, but has since passed away from cancer. Enjoy my friends.