Although I am not a reader of fiction, and do not consider myself experienced or qualified enough to offer literary critiques of such work, I knew that I would enjoy this particular work because of Lewis' ability to speak deeply through prose.
The story is a myth retold (one I was previously unfamiliar with), of Cupid and Psyche. Thus the story is set in the pre-Christian world, in the kingdom of Glome. It is told from the first-person perspective of Orual, the unattractive older half-sister of the quite beautiful Psyche. There is a battle between logic an mythological belief that happens with Orual, as the gods require that Psyche be given over to them. Struggling to believe in these gods and the reasoning that comes from her teacher, Orual sets out to find Psyche (at least, for proper burial) only to discover that she is living in the valley of the gods.
Psyche claims to live in a marvelous palace, where her lover comes to her in the dark - for she has been forbidden to see his face. The tension is heightened when Orual does not see this palace, nor does she accept that the gods have been caring for her (perhaps Psyche is being drugged or tricked by bandits living in the mountains). The struggle thus begins on what has happened to Psyche, and what Orual must do to save her.
It has been said that Lewis himself was somewhat haunted by the story of Cupid and Psyche for most of his life, never being able to let it out of his mind. In his initial concept of rewriting it, before he was a Christian, he had it in mind to place Orual in the right and the gods in the wrong. But that has changed.
I confess that I often need assistance to get to the deeper levels of narrative and story, and Lewis' writing is good enough to be no exception. I am grateful that Lewis himself has reflected on this story, "An author doesn't necessarily understand the meaning of his own story better than anyone else, so I give my account of Till We Have Faces simply for what it is worth."
Although the story is set within the pagan world of the gods, there are parallels to Christian conversion. Psyche becomes an instance of someone making the best of their pagan religion but always and constantly on the path to finding the one true God. Orual then becomes the possessive controller who cannot stand to see Psyche in such a deep and compelling love.
Thus, according to Lewis:
"Of course I had always in mind its closer parallel to what is probably happening at this moment in at least five families in your home town. Someone becomes a Christian, or in a family nominally Christian already, does something like becoming a missionary or entering into a religious order. The others suffer a sense of outrage. What they love is being taken from them. The boy must be mad. And the conceit of him! Or: is there something in it after all? let's hope it is only a phase! If only he had listened to his natural advisers. Oh come back, come back, be sensible, be the dear son we used to know! Now I, as a Christian, have a good deal of sympathy with those jealous, suffering, puzzled people (for they do suffer, and out of their suffering much of the bitterness against religion arises). I believe the thing is common. There is very nearly a touch of it in Luke II.38, 'Son, why hast thou so dealt with us?' And is the reply easy for a loving heart to hear?"