From the cloistered world of Oxford they created two of the best-loved fantasy realms in English literature which themselves inspired blockbuster movies.
CS Lewis and JRR Tolkien were the closest of friends, one struggling to make his fantasy world of Middle Earth a literary reality, the other trying to convince friends his first book about Narnia deserved to be published.
But new research has revealed that their friendship was riven by the most bitter and personal of rows on everything from literature to religion and even their choice of spouse.
The fascinating revelations about their real relationship have been made by film-maker Norman Stone while researching a new drama-documentary on the life of Lewis. Stone, who made the award-winning movie about Lewis, Shadowlands, talked to mutual friends of the literary pair as well as examining documents in minute detail.
His portrayal of their frequent and occasionally destructive bickering comes on the eve of one of the most eagerly-awaited movies of the year, the £129m The Chronicles of Narnia: The Lion the Witch and the Wardrobe, and follows the astounding critical and commercial success of the Lord of the Rings trilogy.
But Stone’s drama-documentary, to be broadcast in December this year, lays bare the sometimes unbearable tension between the two writers whose work would inspire Hollywood.
In CS Lewis, Beyond Narnia, Lewis and Tolkien are shown having a violent argument about The Lion, The Witch and The Wardrobe. Lewis wrote afterwards: “No harm in him, only needs a smack or so.”