I'm a devoted Hitchcock fan. Over the years, I've tried to like Topaz, but for some reason, it just doesn't work for me. I don't know why.
If you like Hitchcock's work, I'll suggest you read The Dark Side of Genius: The Life of Alfred Hitchcock, by Donald Spoto. It shatters many illusions about the great director while reinforcing others. It just may be the definitive work on Hitchcock.