I read this one years ago, knowing little about Christie and nothing about Tommy and Tuppence, having picked it up because of the Shakespeare reference in the title. At this point I don't remember anything after the set-up except that there's a character in it named Mr. Eccles, which was the first time I'd encountered that surname outside The Goon Show. I keep meaning to re-read the whole series one of these days, but there's so much else to do...