Possible Clues:

• "Death on the Nile" novelist Christie
• Christie's starts to auction goods, I see, over time
• She expresses surprise about American gun
• 1979 film starring Dustin Hoffman
• --- Christie, crime writer
• Bertie Wooster’s fearsome aunt
• ___ Christie
• 1979 drama film starring Vanessa Redgrave
• Poirot creator Christie
• "Queen of Crime" Christie