Looking through my email files, I found one I had sent to myself and forgotten about!
I think it is a post I originally wrote for some subforum at the Harry Potter discussion forum Leaky Lounge, in answer to someone asking for more info on books by C.S. Lewis, other than The Chronicles of Narnia.
I read most of C.S. Lewis's works. A good place to start if you want to get aquainted with his basic theology is Mere Christianity. A more personal touch on his conversion can be found in his autobiography Surprised by Joy.
I haven't heard of a "complete works" edition but I think most of his books are getting reprinted every now and then.
The Space Trilogy consists of Out of the Silent Planet, Perelandra, and That Hideous Strength. These are not children's books but intended for more grown-up readers. Like the Narnia books they deal with good and evil, and stretch from creation till the end of the world themes. In the first two the main character Ransom, travels into space and lands on other planets, where evil is not yet found. But evil is introduced into these worlds by two other humans, Weston and Devine. The last book takes place on Earth but with "intervention" from otherworldly beings that Ransom has met in the previous books.
Lewis manages to intertwine ideas from for example Greek and Roman mythology with Christian theology; he also manages to combine speculations about life on other planets with classical Christianity. His God is God of all the Universe, whether there are other worlds and other kinds of creatures out there or not.
After Lewis's death, an unfinished manuscript was also found where the character Ransom is involved. This story was never finished by Lewis (He probably started it after the first space novel but abandoned it for other ideas). It contains ideas about time-travelling. As far as it goes, it has been published posthumously in The Dark Tower And Other Stories, together with a few other fragments and short stories, edited and with a preface by his friend Walter Hooper; who has also written a biography about Lewis together with Roger Lancelyn Green.
Another work of fiction is Till We Have Faces. It is a "reworking of the myth of Cupid and Psyche". I read it a couple of times but found it hard to understand. Maybe I should reread it again now when the internet makes it so much easier to look things up.
My own photo, taken through plexiglass window at the zoo.
(Also published not long ago at Soaring through the World)