Does 'I have been visiting an old woman in the village, she explained, "and as Lawrence told me you were with Monsieur Poirot I thought I would call for you."' serve to directly refute the premise presented in 'I am good friends with Monsieur Poirot.'
I have been visiting an old woman in the village, she explained, "and as Lawrence told me you were with Monsieur Poirot I thought I would call for you."###I am good friends with Monsieur Poirot.