Oh, dear ! My sloppy grammar has caused Stilly River Sage to wax wroth.

By some TV adaptations are purer "whodunnit" than the original Miss Marple novels, though not the Poirot mysteries, I meant to say that the Poirot mysteries were generally better written than some of the Miss Marple stories, and therefore the TV episodes did not need to improve on the original to the same extent.

Evil under the Sun did slightly violate the unwritten rules, but few of the David Suchet adaptations do. Murder on the Orient Express was unimpeachable whodunnit, but ruined by Albert Finney's hamming.