Hi FriendofNarnia2, I think you will need to contact the Mark Gordon company, who hold the 'rights' for this movie, IF you want to develop it in conjunction with the movie. They must have a department looking at merchandising, who would be in contact with the Estate.
If it is unrelated to the movie (unlikely) then you would probably contact the Estate first.

Thanks Coracle!

How can you know if something is on conjunction with the movie or not? Maybe if it was a Voyage of the Dawn Treader themed game I'd contact the Estate, but if it is a Silver Chair themed game I'd talk with the Mark Gordon Company? Is that sort of the way you see it?

Also, do you have a link for how to contact The Mark Gordon Company and the Lewis Estate? I'm having a hard time finding the info.

My two cents is that it doesn't matter if your inspiration for the Silver Chair is the book or movie. With Silver Chair currently in production if you can pitch to the merchandising department it'd be a win-win. Fans would get a quality game and you'd get a wider distribution.

My two cents is that it doesn't matter if your inspiration for the Silver Chair is the book or movie. With Silver Chair currently in production if you can pitch to the merchandising department it'd be a win-win. Fans would get a quality game and you'd get a wider distribution.

True true! The game would be based on the book though, since I really have no idea what changes they might make to the film.

Here are a couple of links, but they don't have contact details. Perhaps try IMDB for the Mark Gordon company?

http://www.narniaweb . com/2017/02/what-we-know-about-the-chronicles-of-narnia-the-silver-chair/

http://www.narniaweb.com/info/cast-crew/

Harper Collins site says:
All permission requests for CS Lewis should go directly to the estate: @narnia.com">rachelchurchill@narnia.com

The C.S.Lewis Foundation gives this full postal address:

The C.S. Lewis Co. Ltd.
First Floor
Unit 4, Old Generator House
Bourne Valley Road
Poole
Dorset
BH12 1DZ
UK

Thanks! Very much appreciated.