I recently stumbled across the information that Avram Davidson had ghost-written two Ellery Queen books, and one of them was this, which happens to be the only Ellery Queen book I've ever read, having purchesed it at a sale of work in, I think, Castleconnell some time during my teens, and which was the weirdest, strangest most haunting murder mystery I've ever read.

1944, Ellery Queen, after a stint as a writer of propaganda films for the war effort in LA, brilliantly depcited in the opening section, gives up and sets off home, driving cross-country in a state of near ecstatic exhaustion, then stumbling on a remote hidden desert valley where a small religious community has lived undisturbed for sixty or seventy years in a peaceful idyll. His coming is foretold, apparently, and heralds something terrible happening, which it soon does when a member of the community is murdered in their most sacred space. How do you solve a murder in a place that has hardly ever known crime?

The mystery itself isn't that difficult to work out, but it is carefully worked through. Of more interest is the strange atmosphere, the scraps of erudition, the murky history of the sect and its odd traditions and how the murder could threaten all of it. It even has a 'and the book turned out to be!' twist, but it works and is played for poignancy rather than a cheap stab at shock.