Related Clues:

• 'Yeah, sure ...'
• "That is so not happening!"
• ''Hah!''
• "Never gonna happen!"
• In a bad way with back? That sounds very sceptical indeed (1'2,3)
• "That's unlikely"
• "I highly doubt that!"
• Skeptic's response
• Cynical comeback
• 'Yeah, that'll happen'
• 'Like that'll ever happen'
• ''A likely story''
• 'Highly doubtful'
• "A likely story"
• '... ___ to say ...'