Related Clues:

• Timely query
• UN immunization agency
• ''What person?''
• 'Seriously?!'
• ''Horton Hears a __!'' (Seuss book)
• '___ knows?'
• Time-traveling Doctor
• With 54-Down, start of a historic telegraph message
• 'Say that again?'
• You-know-__
• First of the five W's
• '___ dat?'
• Thaw out, eh?
• First word of the Declaration of Independence
• Declaration of Independence's first word