"You heard a woman."
"It was your sister or yourself."
"Or one of a million others."
Nigel thumped out his points on the top of a revolving bookcase.
"I had the house watched. No woman entered or left till yesterday. Barring two nurses, and they're accounted for. You or your sister must have left here yesterday."
"And not come back?"
"No."
"Well, that makes it much easier, doesn't it? If one went out and never came back, and you find the other here the following day, it looks ... I mean to say, a perfectly impartial outsider might think, that it was my sister who got away and I who remained behind."
"Exactly. And it's on the same simple reasoning that Aintree will be arrested."
Nigel crooked his umbrella over his arm and slowly drew on his gloves. It was a moment of exquisite, manifest triumph. Elsie stood disarmed and helpless; Sylvia was too proud to ask terms of such a conqueror.