"Which room?" whispered the detective.
"At the top of the stairs," Frank told him.
At that moment the door of the workroom opened and they could see a man run out onto the landing.
"Who's there?" called out a startled voice.
It was Markel. He was clearly silhouetted in the light from the workroom.
"The police," answered Mr. Hardy. "Put up your hands! We have you covered."
In reply, Markel flung himself flat on the floor, there was a streak of crimson, and a revolver shot roared out. Mr. Hardy and the Secret Service men had their weapons ready and they replied with a fusillade of shots.
The light in the room at the head of the landing had gone out. With a bound, Mr. Hardy reached the stairs, then raced up the steps. When he reached the landing, however, he found that it was deserted. Markel had escaped the bullets and had crawled back into the room, for the door was closed.
Fenton Hardy launched himself against the door of the workroom, but it did not budge. He could hear sounds of voices, a noise of banging and of running about in the room beyond.
The Secret Service men and the two boys reached the landing.