This applies to both the books and film.
The expression "so far back in the closet they're in Narnia" is used humorously to describe a gay person who is deeply
closeted,
often to the extent of not realizing their own sexual orientation, or
not admitting it to themselves. Such people are also sometimes referred
to as "Narnians".--
Wikipedia entry on The Chronicles of Narnia in Popular Culture And the actor that played Edmund Pevensie,
Skandar Keynes is an atheist. Not only that, but he is the great-great-great grandson of Charles Darwin.
It makes me wonder, thou not too seriously, how the Christian Right spun that last one. The first fact I just find ironic for the sake of it.