Related Clues:

• _____ dunnit
• Impatient query
• Investigator's pronoun
• ''Horton Hears a __!''
• ''Are you serious?!''
• "Quadrophenia" group, with "The"
• "Are you kidding?"
• Immortal first baseman
• Word to the pourer
• One of a reporter's Five W's
• 'Sez ?'
• "Guess ___?"
• 'I can't hear you'
• ''On what date?''
• Confusing first baseman of fiction