There's a continuity error when Ariadne Oliver visits Anne and Rhoda. She suggests Shaitana was Syrian, even though she and Poirot were established not to know where Shaitana was from in an earlier scene. Wheeler later reveals that Shaitana was indeed Syrian, but he was the only one who knew. I think it's just a mistake, though, and doesn't represent any of the established tropes.
There's a continuity error when Ariadne Oliver visits Anne and Rhoda. She suggests Shaitana was Syrian, even though she and Poirot were established not to know where Shaitana was from in an earlier scene. Wheeler later reveals that Shaitana was indeed Syrian, but he was the only one who knew. I think it's just a mistake, though, and doesn't represent any of the established tropes.