"I'll join you as soon as she's asleep. If nothing happens we've simply got to repeat the performance till something does. I wish I knew what they were after."

"Meanwhile," said Peter, consulting his wrist-watch, "it's already half-past seven, and we're dining with old Ackerley at eight." He stopped suddenly. "By Jove! Think that mysterious pair will get going in the house while we're out? I hadn't thought of that."

"No," said Charles. "The little chap spoke of one of us "waking up."'

"All the same," Peter said, "I move that we don't stay late at the White House."

In spite of what Charles said, Peter felt ill at ease about leaving the Priory in the sole charge of the Bowers. Clever crooks, he was sure, would know the movements of their prospective victims. Yet if burglary were mediated surely these particular crooks would find it an easy enough task to break into the Priory without shadowing the place at all hours, and searching for - what? There he found himself up against a blank wall again. Strange and his odd companion had certainly been looking for something, but what it was, or what connexion it could have with a possible burglary he had no idea.

He realised that his mind harped all the time on burglary, and was forced to admit to himself that it was an improbable solution. There was very little of value in the house, and if anything so unlikely as hidden treasure were being sought for it was incredible that the thieves should have waited until the house was tenanted before they made an attempt to find it.

Charles obviously connected the affair of the previous evening with Strange, in which case it looked as though Strange's primary object was to frighten the tenants out of the house. He wondered whether he would seize the opportunity this dinner-party afforded to stage another, and even more nerve-racking, booby-trap.

Peter arrived at the White House with the rest of his family just as eight o'clock struck. His sisters, who had reviled both him and Charles for staying out so late, drew two sighs of relief.

"Scaremongers," said Charles. "I told you it wouldn't take us ten minutes to get here."

They had walked to the White House across their own grounds, a proceeding which Celia had condemned, dreading the return late at night, but which had been forced on them, not only on account of its convenience, but on account also of the car, which had developed slight magneto trouble, and refused to start.