From a window of the house Detective Bateman watched the result of Alan’s brotherliness with an interested eye before hurrying back to the library.

“They’ve gone,” he said. “And I think your brother and sister are coming back. I’m sure it’s your brother and sister,” he added with a smile.

“Oh,” said Cynthia. “Well, we’d better get this absurd thing off then.” She extended a slender wrist, and Detective Bateman did something with a key. The wrist was freed. “I think,” Cynthia smiled, “that Dora really ought to keep hers on a lot longer. However, perhaps we mustn’t be too harsh with her.”

“What on earth——?” cried Dora, finding her voice with an effort as the detective bent over her wrist in turn.

“Yes, dear,” said Cynthia sweetly. “Quite. By the way, I don’t think you’ve ever met Mr. Priestley, have you? Take that dreadful beard off, Mr. Priestley, and be introduced properly.”

For a couple of moments there was silence; then babel, produced largely by Dora, ensued.

“Cynthia, you loathsome person,” observed Miss Howard, some two minutes later, “just be quiet a minute and let me get this straight. You say the Superintendent really isn’t a superintendent at all, but a friend of Mr. Priestley’s?”

“Quite correct,” beamed that gentleman. “His name is Adams. We were at school together.”

Dora digested this. “And the other two are friends too?”

“All friends of mine,” agreed Mr. Priestley, without a single sign of compunction.