There is a nice post about Charles Williams by Paul Blair over on Transpositions, the blog of St. Andrews University. Here is the beginning:
Charles Williams is utterly distinctive. Some scholars think that Williams has something to say that both resonates with and challenges postmodernity. His work deals sympathetically with man’s suffering, contradictions, and impossibilities, in addition to the accompanying skepticism. Many postmoderns can find some common ground with his sensitivity to suffering and skepticism, but he also challenges the inherent relativism of our day with a fresh perspective of orthodoxy, through his fictional narratives as well as his theological works. This perspective aids one to think from a new standpoint and gain a different frame of reference, centering in Christ’s identification with man through His Incarnation and especially His Passion.