I was thinking about the phrase “the smile never reached his eyes”. It's quite a common phrase, and it indicates an insincere facial expression, right? Or, rather, an insincerely positive facial expression. Is there a common phrase for an insincerely negative facial expression? There probably isn't a need for one, but if there was, what would it be?
The frown never reached his… eyebrows? His scowl was only skin-deep?