There are only four books in the main series, and none of them are too terribly long. But if you’re a completist, there’s no limit to how deep you can dive into what the author called his "legendarium.

If you've seen The War of the Rohirrim, you may be wondering where you can read the story of Helm Hammerhand — but aren't sure where to start. We've got you covered.

The War of the Rohirrim anime debuted in theaters on December 13, but you can already preorder the limited-edition 4K Blu-ray release for $38 at Amazon.