His manner was perfectly natural.
"Yes," said Poirot thoughtfully, "that describes Mademoiselle Katherine very well. It is very English, that phrase there, and Mademoiselle Katherine, she also is very English."
Derek remained perfectly still without answering.
"And yet she is sympathique, is it not so?"
"Yes," said Derek; "there are not many like her."
He spoke softly, almost as though to himself. Poirot nodded significantly. Then he leant towards the other and spoke in a different tone, a quiet, grave tone that was new to Derek Kettering.
"You will pardon an old man, Monsieur, if he says to you something that you may consider impertinent. There is one of your English proverbs that I would quote to you. It says that 'it is well to be off with the old love, before being on with the new.'"
Kettering turned on him angrily.
"What the devil do you mean?"
"You enrage yourself at me," said Poirot placidly. "I expected as much. As to what I mean—I mean, Monsieur, that there is a second car with a lady in it. If you turn your head you will see her."