THE FORDWYCH CASTLE MYSTERY
had been Joan's bedroom, I found that it was locked, and that this key fitted into the lock. Roonah had locked that door herself on her own side—she was afraid of her mistress. I knew now that I was right in my surmise. The prayer-book is a Roman Catholic one. It is heavily thumbmarked there, where false oaths and lying are denounced as being deadly sins for which hell-fire would be the punishment. Roonah, terrorised by fear of the supernatural, a new convert to the faith, was afraid of committing a deadly sin.
"Who knows what passed between the two women, both of whom have come to so violent and terrible an end? Who can tell what prayers, tears, persuasions Joan Duplessis employed from the time she realised that Roonah did not mean to swear to the lie which would have brought her mistress wealth and glamour until the awful day when she finally understood that Roonah would no longer even hold her tongue, and devised a terrible means of silencing her for ever?
"With this certainty before me, I ventured on my big coup. I was so sure, you see. I kept Joan talking in here whilst I sent Pegram to her room with orders to break open the locks of her hand-bag and dressing-case. There!—I told you that if I was wrong I would probably be dismissed the force for irregularity, as of course I had no right to do that; but if Pegram found the papers there where I felt sure they would be, we could bring the murderer
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