Much as The Robots of Death and Blake's 7 both ended up as prequels to Kaldor City even though they aren't related to each other, The Manlet and Sil Marillion both ended up as prequels to Lord of the Rings even though they aren't related to each other.
Smaug White, played by Sherlock, kicks the Seven Dwarves out of their house. Eventually, Gandalf, played by The Great Intelligence, gets sick of hearing the "Hi-Ho" song and decides to hire a burglar to steal a massive hoard of gold and jewels for them, plus an entire mountain, because obviously their DM ignores the encumbrance rules.
Gandalf hires a manlet, played by Watson, as his thief. He doesn't want to join in, but the dwarves sing "Hi-Ho" over and over until he relents.
They do a shitload of grinding against goblins and orcs and slimes to level up, but they still fail to steal the entire mountain without the dragon noticing, so he wakes up and gets shot down by Green Arrow.
Meanwhile, Gandalf wanders off on a side quest to find a neck romancer, who's also played by Sherlock for some reason. Also, somewhere along the way, Watson finds a magic ring that probably won't turn out to matter.
Then everyone gets bored, so they have a war between all the good fantasy races, but it gets interrupted by a war against all the bad fantasy races, and then the eagles show up right at the very end, as usual, after half the heroes are dead.
- In the movies, all of the manlets in the movie are played by real human beings, but one of the wizards who isn't in the book is played by a manlet. You may have heard him mention that he's in it.
- Fucking eagles.