CS Lewis wrote a letter insiting that Narnia should never be adapted with live actors, calling it "blasphemy" and saying that he'd consider a cartoon (but not from Disney), but never allow human actors to portray his Narniacs. Now, from the letter he's talking about human actors in animal costumes, but it's clear he's also skeptical about the whole live action thing in general.
(Why do you 'Dr' me? Had we not dropped the honorifics?) As things worked out, I wasn't free to hear a single instalment of our serial [The Magician's Nephew] except the first. What I did hear, I approved. I shd. be glad for the series to be given abroad. But I am absolutely opposed – adamant isn't in it! – to a TV version. Anthropomorphic animals, when taken out of narrative into actual visibility, always turn into buffoonery or nightmare. At least, with photography. Cartoons (if only Disney did not combine so much vulgarity with his genius!) wld. be another matter. A human, pantomime, Aslan wld. be to me blasphemy.
All the best,
C. S. Lewis
[Letter to BBC producer Lance Sieveking (1896-1972), who has written at the top: 'The Magician's Nephew' and, after the address, the phone number "62963".]