Movie vs. Book:There And Back Again

On a journey to re-claim The Lonely Mountain and Dale, the dwarves accidently set Smaug free which will danger Lake Town. Bard, a man who has a black arrow that will kill the beast is in jail. Without him the dragon will destroy them. Even if they do kill Smaug, how will they deal with The Necromancer and Azog? Will they get help from the elves? Dale? Men? ANYBODY? We will just have to wait and see.