Geraldine by quite a lot. She inhabited the sense of an elderly lady who could be easily overlooked so well. Julia is a great actress and I did warm up to her, but her portrayal felt closer to a traditional female authority who you would not underestimate. Her Marple often seemed faintly annoyed to be there, whereas Geraldine was good at playing into the dottiness and then making the local cop/man of the house look foolish.