“Did you know Doctor Von Blon was here last night?” he asked when the butler appeared.
The man shook his head.
“No, sir. I was quite unaware of the fact.”
“That’s all, Sproot. And now please tell Miss Sibella we’d like to see her.”
“Yes, sir.”
It was fifteen minutes before Sibella put in an appearance.
“I’m beastly lazy these days,” she explained, settling herself in a large chair. “What’s the party for this morning?”
Vance offered her a cigarette with an air half quizzical and half deferential.
“Before we explain our presence,” he said, “please be good enough to tell us what time Doctor Von Blon left here last night?”
“At a quarter of eleven,” she answered, a hostile challenge coming into her eyes.