Some months ago I read Howard Blum's 'I Pledge Allegiance' about the Walker spy ring. Looking for a quick read, I noticed Barron's book on the same subject besides Blum's on the bookshelf and decided to give it a try. It turned out to be a good choice. While Blum handles the story basically as a biography of Walker and his associates, most of whom were family members, Barron approaches the story from the perspective of the governmental investigators of the conspiracy. Also, while Blum is, judging from his other books, a bit of a liberal, Barron, a long-time editor of the 'Readers Digest', is a virulently anti-communist right-winger. The cited facts of the case are compatible, but the approaches are very different.
Barron is a pretty good writer, not in any stylistic sense, but in that he carries the narrative along quickly, allowing the reader to become absorbed, forgetful of the act of reading.