It has long been a source of wonder to me why the leading criminological writers—men like Edmund Lester Pearson, H. B. Irving, Filson Young, Canon Brookes, William Bolitho, and Harold Eaton—have not devoted more space to the Greene tragedy; for here, surely, is one of the outstanding murder mysteries of modern times—a case practically unique in the annals of latter–day crime. And yet I realize, as I read over my own voluminous notes on the case, and inspect the various documents relating to it, how little of its inner history ever came to light, and how impossible it would be for even the most imaginative chronicler to fill in the hiatuses.