Bilbo Baggins lives in a very comfortable Hobbit hole. That's until Gandalf the Wizard arrives with a company of Dwarves to take him off on an adventure to steal treasure from Smaug the Dragon.
On the way they encounter Elves, Goblins, giant spiders and Trolls. Bilbo also has a run in with Gollum, who has a very special ring.
They get to the Dragon and find that they have started a war on the way. Smaug is killed, and Bilbo and the Dwarves get a load of treasure. Bilbo goes home with his loot - and the ring...