Harris chose Joan as the subject of a play because he was enchanted by her story and wanted to communicate it. Unfortunately the story is not well suited to the Harrisian style and Harris was no dramatist, though he persisted in the illusion that he was. His enthusiasm for this ill-advised piece does however indicate that despite his rakish reputation he was still at heart something of a sentimental idealist.
Harris saw certain figures, such as Joan and Jesus, as exemplifying a sort of goodness that deep down he thought he himself possessed: courageously non-comformist, true to their ideals, outspoken, unwavering. He often expressed the desire to write a life of Jesus, but judging by this effort it is as well he did not. Shaw could not really make much of the story of St. Joan: it is unsurprising that Frank would fail by a greater margin.
The most interesting part of this book is the introduction, in which Frank reproduces his correspondence with Shaw about it. Shaw described the play as 'idiotic', which is unfortunately all too accurate. The copy I obtained had many of its pages still unopened, and it is not hard to see why. As far as I am aware the play has never been mounted, although it would make a reasonable school production: it is short, simple-minded and entirely suitable for children.