The Chinaman bowed and walked to the wall. The old man pressed the button while his attendant walked through the opening. The wall closed. The old man stared from the window.
Dusk was gathering. Lights were glimmering on the Harlem. Shellmann crept across the room and drew the shade of the single window. He turned on a small wall light. He drew a loaded revolver from the desk drawer. He sat with the gun poised.
“Tonight,” he muttered happily. “Tonight — two more! They die — like those heads dropped off in Shanghai! But I must watch. Danger comes after dark. I can depend on Luke—”
His voice trailed away. His head began to nod. The hand that held the revolver was lowered to the desk.
The gray head rested on the arm. The old man slept.
AT headquarters, Joe Cardona paced back and forth, smiting each fist alternately against the opposite palm.
“Double Z!” he growled. “If they’d only give me a chance! This business tonight — well, I’m guarding the place. Men inside the house. No one suspects this last letter — it’s only natural that I might have men up at Wade’s!
“They think Wade’s dead! If I told them different, it would save my skin. But what if I do tell? Then he’s prey for Double Z. I’ve got one chance to get the man himself. ‘To die by my own hand.’”
Cardona was repeating words that he could not forget. He brought his fist against his palm and cried aloud:
“If I could only pull something now! Only how” — he walked back and forth a full minute, then repeated — “if I could only find out where those letters come from—”