Yale looked at him suspiciously. It did not seem the moment or the occasion for flippant talk, and Inspector Parr’s tone was undoubtedly flippant. Chapter XLI. Who is The Crimson Circle? Yale learnt no more details than those he had already read, and took a taxi to his city office, which he had not visited for two days. The escape of Thalia Drummond was a much more important affair than Parr seemed to think. Parr! An awful thought occurred to Derrick Yale. John Parr! That stolid, stupid-looking man--it was impossible! He shook his head, yet put his mind resolutely to the task of piecing together every incident in which Inspector Parr had figured, and in the end: “Impossible!” he muttered again, as he walked slowly up the stairs to his office, declining the invitation of the lift-boy. The first thing he noticed when he unlocked the door was that the letter-box was empty. It was a very large letter-box, with a patent flap device, designed so that it was impossible for an outside pilferer to extract any of its contents. The wire cage reached almost to the floor, and letters that came through the slot in the door had to fall through revolving aluminium blades, which made the letter thief’s task a hopeless one. And the letter-box was empty! There was not so much as a tradesman’s circular. He closed the door quietly and went into his own room. He took no more than a pace into the interior and then stopped. Every drawer in his desk was open. The little steel safe by the side of the fireplace, concealed from view by the wooden panelling, had been unlocked, and the door was now open. He looked under the desk. There was a tiny cupboard, which only an expert could have found, and here Derrick Yale had kept the more intimate documents connected with the Crimson Circle case. He saw nothing but a broken panel and the mark of the chisel that had wrenched it free. He sat for a long time in his chair, staring out of the window. There was no need to ask who was the artist. He could guess that. Nevertheless, he made a few perfunctory inquiries, and the lift boy supplied him with all the information he needed. “Yes, sir, your secretary has been this morning, the pretty young lady. She came in soon after the offices were open. She was only here about an hour, and then she left.” “Did she carry a bag?” “Yes, sir. A little bag,” said the boy. “Thank you,” said Derrick Yale, and went back to head-quarters, to pour into the phlegmatic Mr. Parr’s ear a tale of rifled desk and stolen documents.