A strained silence followed.

"Please come in," Isobel said coldly. "I will see if dad is in."

She and her visitors went into the house, leaving Allen lost in amazement.

In a moment or two Isobel returned.

"Tell me," Allen asked in a melodramatic stage whisper, "have they confessed?"

"Not a thing. What can have made them behave like that?"

"I thought it was my presence that was worrying them. After all, if he's murdered his mother-in-law for her lump sugar he'd hardly like to tell you about it before a comparative stranger."

"Perhaps," suggested Isobel, "they've come to clear up the mystery of Denmore Manor."

They both laughed. The Manor Mystery had become a family jest at Dunwater.

"What's the latest about it?"