Murder on the Orient Express
Her small toad-like face looked even yellower than the day before. She was certainly ugly, and yet, like the toad, she had eyes like jewels, dark and imperious, revealing latent energy and an intellectual force that could be felt at once. (2.6.47)
"I think, Madame, that your strength is in your will – not in your arm."
She glanced down at her thin, black-clad arms ending in those claw-like yellow hands with the rings on the fingers.
"It is true," she said. "I have no strength in these – none. I do not know if I am sorry or glad." (2.15.70-72)
"It might be a question of the influence of mind over body," said Poirot. "Princess Dragomiroff has great personality and immense will power. But let us pass from that for the moment." (3.2.40)