I don't have a copy, sorry PT!
I think Zenith and it's surrounding state Winnemac were used in several of Lewis' books. Here's what it says about Zenith in the wiki entry:
Zenith is a typical midsize Midwestern city. Lewis was very critical of the similarities between most American cities, especially when compared to the diverse—and by his lights, more culturally rich—cities of Europe. Frowning on the interchangeable qualities of American cities, he wrote: "it would not be possible to write a novel which would in every line be equally true to Munich and Florence." This is not true of Zenith, Babbitt’s literary home. Zenith is a fictitious city in the equally fictitious Midwestern state of “Winnemac,” adjacent to Ohio, Indiana, Illinois, and Michigan. (Babbitt does not mention Winnemac by name, but Lewis's subsequent novel Arrowsmith elaborates on its location.) When Babbitt was published, newspapers in Cincinnati, Duluth, Kansas City, Milwaukee, and Minneapolis each claimed that their city was the model for Zenith. Cincinnati had perhaps the strongest claim, as Lewis had lived there while researching the book. Lewis's own correspondence suggests, however, that Zenith is meant to be any Midwestern city with a population between about 200,000 and 300,000.
Alison - it's so good to hear from you! I didn't even know Keeper of the Flame was
a play! It's certainly not exciting, but I liked the foreboding of evil it gave off, and again, those references to Citizen Kane
were exceptionally strong, to my mind. It's quite thoughtful, and the black and white photography is worth checking out. Lately I've been into those transition movies at MGM - late forties attempts at noir that weren't always successful because the studio was bulging with excess... it seems to take a 'less is more' attitude to do noir well. Or maybe it's not even attempting to be noirish, but more like All the King's Men or something of that nature. Not great, but interesting, certainly.
EDITED: Well, I have to change my post here, because I didn't realize that Keeper of the Flame was made in 1943! That gives it a different spin altogether, not late forties at all.... Now I think it really was influenced more by Citizen Kane.