“You are quite fixed upon detaining me?”

“Quite,” said Stokes, watching him closely.

In one long stride Brinn was through the doorway, telephone in hand! Before Stokes had time to move, the door closed violently, in order, no doubt, to make it shut over the telephone cable which lay under it!

Detective Sergeant Stokes fell back, gazed wildly at the false books for a moment, and then, turning, leaped to the outer door. It was locked!

In the meanwhile, Nicol Brinn, having secured the door which communicated with the study, walked out into the lobby where Hoskins was seated. Hoskins stood up.

“The lady went, Hoskins?”

“She did, sir.”

Nicol Brinn withdrew the key from the door of the room in which Detective Sergeant Stokes was confined. Stokes began banging wildly upon the panels from within.

“That row will continue,” Nicol Brinn said, coldly; “perhaps he will shout murder from one of the windows. You have only to say you had no key. I am going out now. The light coat, Hoskins.”

Hoskins unemotionally handed coat, hat, and cane to his master and, opening the front door, stood aside. The sound of a window being raised became audible from within the locked room.