ng, Captain. You are welcome to add him to your growing
collection of prisoners."

For answer the young man whipped out a revolver and fired point-blank at
the criminologist. His was a ready trigger finger. But he was no swifter
than the convalescent detective on the couch, who had swung a six
shooter from a mysterious fold of the steamer blanket, and planted a
bullet into the man's shoulder from the rear.

As the smoke cleared away, Shirley straightened up from the crouching
position on the floor which had saved him from the assassin, and dragged
the wounded criminal to his feet. The handcuffs clicked about his wrists
before the young man had grasped the entire situation. Cleary and three
others of the private force were in the room.

"I've got to hurry along now, Captain. Just let him know that his Chief
is captured and the sooner he turns State's evidence the better it will
be for him. The District Attorney might make it lighter, if he helps.
I'll be back this evening if I can." And Shirley hurried away, leaving
much surprise and bewilderment in every mind.

Cronin was equal to the task of picking up the threads, and under
his sarcasm, and Cleary's rough arguments, the prisoner admitted some
interesting matters about the mysterious employer whose face he had
never seen. But Shirley's task was far from completed.

CHAPTER XX. A DOUBLE ON THE TRAIL

Shirley walked up to the Hotel California, at the door of which he met
Warren and Taylor just leaving. They looked somewhat embarrassed but his
manner was cordiality itself.

"Sorry you are going. I was just stepping up to see Miss Marigold. Won't
you come back?"

His invitation was refused. Then Shirley urged Warren to be his guest
at the club for dinner that evening. This was accepted with a surprising
alacrity. So, he left them, and was soon talking with Helene.

"You missed a curious little sociable party," she assured him. "They
tried to quiz me, and I confess that I worked for the same purpose--no
results on either side. But, Warren had an unusual telephone call, which
disturbed him so much that he hurried away, sooner than he had planned."

Shirley recounted his explorations of the afternoon, with the
explanation of Reginald's disturbance. It was certain now that the
leader of the assassins had something to cause uneasiness,--enough to
take his mind off the campaign of murder and blackmail.

"But he will try to get you out of the way," was her anx