The thrust pierced Anderson's armor. For once he seemed at a loss.Here was something he had omitted from his calculations. But hedid not give up. He was about to retort when - crash! thud! - thenoise of a violent struggle in the hall outside drew all eyes to thehall door.

An instant later the door slammed open and a disheveled young manin evening clothes was catapulted into the living-room as if slungthere by a giant's arm. He tripped and fell to the floor in thecenter of the chamber. Billy stood in the doorway behind him,inscrutable, arms folded, on his face an expression of mildsatisfaction as if he were demurely pleased with a neat piece ofhousework, neatly carried out.

The young man picked himself up, brushed off his clothes, soughtfor his hat, which had rolled under the table. Then he turned onBilly furiously.

"Damn you - what do you mean by this?"

"Jiu-jitsu," said Billy, his yellow face quite untroubled. "Prettygood stuff. Found on terrace with searchlight," he added.

"With searchlight?" barked Anderson.

The youthful man turned to face this quite new enemy.

"Well, why shouldn't I be on the terrace with a searchlight?" hedemanded.

The detective moved toward him menacingly.

"Who are you?"

"Who are you?" said the youthful man with cool impertinence, givinghim stare for stare.

Anderson did not deign to reply, in so many words. Instead hedisplayed the police badge which glittered on the inside of theright lapel of his coat. The youthful man examined it coolly.