For those who loved the Narnia books and/or those who have read his papers, the biography on the BBC is worth catching. It paints a poignant picture of the sensitive academic behind the written word.
There were a number of great writers who emerged at the same time as C.S.Lewis and J.R.R. Tolkien. If you are not familiar with his works, I highly recommend E.R. Edison - The Zimiamvian Trilogy and The Worm Ouroboros for beautiful prose and wonderful characters.