Related Clues:

• '___ Misbehavin''
• 'No way!'
• 'Huh-uh'
• Nah
• '___ That a Shame' (#1 hit for 18-Across)
• At all
• Isn't wrong?
• 'It ___ pretty!'
• 'Nah!'
• Slangy denial
• Gershwin's 'It ___ Necessarily So'
• 'Uh-uh'
• 'Don't sweat it'
• 'Over my dead body!'
• Picnic pest, in this puzzle?