We are only shown of the 31 letters from Screwtape, from which we would come to understand the efforts of Wormwood, as well as the human in walking the Christian path.
Interesting movie it'll be I suppose. Hmm...I remember seeing the book in my brother's library cupboard. Maybe I should go take a read.
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Walden media, home of one hit wonder Narnia (not for long- Prince Caspian hits this year) and wholesome family underperformers (Charlotte's Web, How to Eat Fried Worms and, possibly, Bridge to Tarabithia) is going back to its Christian moneymaker by announcing its next project: C.S. Lewis' The Screwtape Letters. If you thought Narnia was a Christian propaganda, check out now.
The Screwtape Letters outline the 31 letters filled with the teachings of the demon Screwtape to his nephew apprentice Wormwood. Based on the frailties and nature of man, Screwtape gives cunning advice on how to lead man into kicking faith in the nuts and giving sin a warm rubdown. Through various subtleties based on the precept that "The safest road to Hell is the gradual one — the gentle slope, soft underfoot, without sudden turnings, without milestones, without signposts," Letters essentially follows Wormwood as he tries to subvert a human simply named The Patient.
Whether or not you believe in the Christian faith, The Screwtape Letters is a fascinating read, giving some pretty keen insights into the justifications of human behavior, faith-based or not. As a credit to its philosophical relevance (if not a huge Christian following) sixty years after its publication as a book (it was originally published in paper The Guardian) The Screwtape Lettersc continues to sell millions of copies.
The film version is being announced as a "mid-budget" live-action piece. No director or casting announcements yet, but Walden and Ralph Winter Productions (X-Men, Fantastic Four) hope to have Screwtape out in 2008.

Screwtape (an Under Secretary in the Lowerarchy) addresses these letters to his subordinate 'nephew' Wormwood, a "very junior Tempter", giving detailed advice on methods of undermining faith and promoting sin, interspersed with observations on human nature and Christian doctrine.
The irony of the tale is that Wormwood's blundering efforts are utterly unable to prevent the soul's salvation, while Screwtape seems incapable of comprehending or acknowledging true human virtue when he sees it.
Versions of the letters were originally published in The Guardian, and the standard edition contains an introduction explaining how the author chose to write his story.
While The Screwtape Letters is one of Lewis' most popular works, Lewis himself claimed that the book was distasteful to write, and he vowed never to write a direct sequel. However, in 1959 he wrote an addendum, Screwtape Proposes a Toast, an after-dinner speech given at to the Tempters' Training College for Young Devils. It first appeared as an article in the Saturday Evening Post.
Plot
"The Screwtape Letters were written by C.S. Lewis and is comprised only of letters written by an ‘affectionate uncle’ named Screwtape, a senior devil. He writes to his nephew/niece, Wormwood, about how to turn people towards the ‘Father below’. Wormwood is a junior tempter trying to convert his ‘patient’ so that he can engulf the patient’s soul."
After the first letter, the Patient converts to Christianity, and Wormwood is given a severe rebuking and threatened with the "usual penalties" at the House of Correction for Incompetent Tempters. Wormwood's task is now to undermine the Patient's faith as well as to tempt him to explicit sins which may result in his ultimate damnation, thus reflecting the Catholic-Anglican view on "mortal sin" and salvation. It is important to note, however, that the nature of the explicit sins is discussed in such a way as to give rise to a thoughtful and reflective speculation of the nature of the distance sin creates between God and Man, as Screwtape explicitly tells Wormwood that the gentle, sliding slope of habitual small sins is better than any grandiose sin (presumably murder, rape, sexual immorality, etc.) for the devils' purposes in terms of damning a patient.
Lewis' use of this 'correspondence' is both varied and hard-hitting. With his usual unexpected mix of lenient and hardline theology, Lewis covers areas as diverse as sex, love, pride, gluttony, and war.