Dastardly expression

As a detective solving the crossword clue ‘Dastardly expression’, my first thought was to consider the meaning of the word ‘dastardly’.
Dastardly implies something cowardly or shameful, which led me to think of expressions that might convey those emotions. From there, I considered various facial expressions that might be associated with such emotions. The word ‘expression’ in the crossword clue was also a helpful hint to focus on facial expressions.

Scowls, sneers, and smirks all came to mind as possibilities, but when I considered the word ‘dastardly’ again, I realized that a sneer would be the most fitting option. A sneer is a facial expression that typically conveys contempt or disgust, often with a self-satisfied or arrogant quality. It can be used to intimidate or belittle someone, which can certainly be considered dastardly behavior.

Drawing on my knowledge of language and human behavior, I was able to solve this crossword puzzle clue by considering the broader context and possible connotations of the words involved. The result was a satisfying conclusion to the mystery of the dastardly expression.