Now they were entering the prison room. No place for anyone to hide here, thought Tuppence, with a sigh of relief, then chided herself indignantly. She must not give way to this foolish fancying⁠—this curious insistent feeling that Mr. Brown was in the house .⁠ ⁠… Hark! what was that? A stealthy footstep on the stairs? There was someone in the house! Absurd! She was becoming hysterical.

Jane had gone straight to the picture of Marguerite. She unhooked it with a steady hand. The dust lay thick upon it, and festoons of cobwebs lay between it and the wall. Sir James handed her a pocketknife, and she ripped away the brown paper from the back.⁠ ⁠… The advertisement page of a magazine fell out. Jane picked it up. Holding apart the frayed inner edges she extracted two thin sheets covered with writing!

No dummy this time! The real thing!