He turned back to the window again, and stared out into the night.

“What has happened?” Howard Torrance demanded. “You’re the only one here who saw it all, Sir Clinton.”

“Someone took advantage of the music from the loudspeaker to steal up close to the window, there, which Mr. Shandon insisted on opening. An air-gun dart was fired into the room and struck Miss Hawkhurst. Luckily, it happened to hit her wrist just where there was some protection—the chain of her watch-bracelet; and that prevented it from going as deep as it might. But if any poison has got into the wound, it may be a serious matter—most serious. That’s all I know, except that I got Dr. Ardsley over immediately, and he has her in his charge.”

“Is there any hope that it won’t be fatal this time?” Howard Torrance asked, anxiously.

Sir Clinton shook his head.

“I know as little as you do. I got the dart out almost immediately, so perhaps the poison hadn’t time to get in its work. That seems to offer some chance of escape. But you’ll need to wait for the expert’s views. I really know nothing.”

“And you don’t seem to be doing anything,” snarled Arthur from the window.

Before Sir Clinton needed to reply, the door opened and Wendover hurried into the room. He was dishevelled, his tie was loose, and his dinner-jacket showed in some places smears of green and brown which he had evidently picked up during his prolonged search. But in his hand he carried the thing Sir Clinton wanted—the air-gun.

“Good man!” the Chief Constable commented, as his eyes rested on the weapon.

At the exclamation Arthur turned back towards the room. His face changed as he caught sight of the thing that Wendover carried.