Related Clues:

• Lip curl
• Villainous facial expression
• Smile weakly
• Mean, mocking smile
• Make one’s disdain plain
• Dastardly expression
• Show of disdain
• Disdainful lip curl
• Condescending smile
• Unkind smile
• Derisive grin or scowl
• Express contempt (Note this answer's last four letters + the first two of 35-Down)