“Open the door, Jerrold!” he cried impatiently. “Don’t play the fool. What’s the matter, old chap?”

“Funny—very funny—isn’t it!” Thomasson exclaimed, his brows knit in mystification.

“Most curious,” declared Sainsbury, now thoroughly anxious. “How long was Mr Trustram here?”

“He dined out with the doctor—at Prince’s, I think—and they came back together about half-past nine. While Mr Trustram was here he was on the telephone twice or three times. Once he was rung up by Mr Lewin Rodwell.”

“Mr Lewin Rodwell!” echoed Sainsbury. “Did you happen to hear anything of their conversation?”

“Well, not much, sir,” was the servant’s discreet reply. “I answered the ’phone at first, and it was Mr Rodwell speaking. He told me who he was, and then asked if Mr Trustram was with the doctor. I said he was, and at once went and called him.”

“Did Mr Trustram appear to be on friendly terms with Mr Rodwell?” asked the young man eagerly.

“Oh! quite. I heard Mr Trustram laughing over the ’phone, and saying ‘All right—yes, I quite understand. It’s awfully good of you to make the suggestion. I think it excellent. I’ll propose it to-morrow—yes, at the club to-morrow at four.’”

Suggestion? What suggestion had Lewin Rodwell made to that official of the Transport Department—Lewin Rodwell, of all men!

Jack Sainsbury stood before that locked door, for the moment unable to think. He was utterly dumbfounded.