Doctor Q had not time to finish the sentence.

The door burst inward.

The Automaton, its eyes aflame, stalked in among them!

CHAPTER XXV

As the Automaton crashed its way into the room all sprang back terrified, aghast.

For this monster, they had felt sure, was now nothing but an inanimate shell of armor, since Balcom was dead.

Yet here it was, stalking toward them and evidently as bent on destruction as ever.

What did it mean?

In an instant Locke had helped Eva through an open window and turned to assist Zita.  But Doctor Q forestalled him and had already taken her in his arms and had fled with her into another room.

For the moment Locke was surprised to see that the Automaton totally ignored him.  Instead, it stalked to the door and wrenched it open.  There, cowering in the hall, in abject terror, was De Luxe Dora.

How and why she had come there was a mystery.  But the Automaton did not hesitate.  It raised its hands and, as it did so, long flashes of blue flame leaped from the steel finger-tips toward the unfortunate woman.  Once she shrieked, then crumpled and fell dead.

The monster then turned its attention to Locke, striding toward him with a menacing gesture.  But the diversion due to Dora had given all just the time they needed to make good their flight.  Locke threw a chair to impede the progress of the monster, and then, as he saw that all the others were safe, he lightly vaulted out of the window himself, to find them waiting for him in the little yard below.

“What do you make of it now—­father?” asked Locke of Doctor Q.  “Balcom is dead.  Who is now in the iron man?”

Doctor Q shrugged.  It was a mystery to him as much as ever, and he seemed unable to throw any light on it.

“But De Luxe Dora,” queried Zita.  “What had she come for?  Why was she struck down—­first?”

Again Doctor Q shook his head.

From the yard they could hear the Automaton’s heavy tread in the room and, as there was nothing to be gained by remaining, they left the yard and hurried away out of the neighborhood.

They had not gone far, however, when Doctor Locke came to a full stop.

“I must go back,” he exclaimed.

For a moment all thought he had again taken leave of his senses.  Yet he was obdurate.

“Miss Brent—­Eva,” he explained, “you know that a grievous wrong has been done your father through me.  He lies ill of that most terrible of diseases, the laughing madness.  I alone possess the antidote, and it is in the laboratory that we have just left.  I pray that that iron beast has not destroyed it.”

At the mere words Locke turned as if to go back for it.

“No, Quentin,” remonstrated his father.  “You must remain to guard Eva.”

“Then I will go,” insisted Zita.  “I am not afraid now.  Even when the monster carried me off I overcame my fear, watched my chance, and escaped from his den, where he left me.  I will go.”