Snatching from a valise a chambermaid’s costume and cap, Yvette swiftly transformed herself into a replica of the unconscious girl. Then picking up the tray and its contents she silently left the room, having poured a few drops of colourless liquid into each of the glasses of brandy.

Kranzler was evidently in a bad temper.

“I tell you,” he said to his companion, “there must be a way out. That infernal—”

There was a knock at the door, and a chambermaid entered with coffee and liqueurs. It was Yvette!

“Would the messieurs require anything further?” she asked as she set down the tray.

“No, that’s all for to-night,” said Kranzler in a surly tone, as he picked up the brandy and drained it with obvious relish. His companion followed suit.

Dick was sitting beside the unconscious girl as Yvette re-entered the room.

“She’s quite all right,” he said, as he watched her narrowly for signs of returning consciousness, “but I must give her a little more just as we are leaving. How did you get on?”

“Splendidly,” said Yvette; “they noticed nothing, and I saw them both drink the brandy as I left the room.”

Ten minutes later Yvette re-entered Kranzler’s room. The two men had collapsed into chairs. Both were sleeping heavily.