Finally he spied the note on the table and snatched it up.  By the dim light he read: 

  You will never live to capture me.  The deadly gas is
  even now killing you.

Locke gasped.  There was the sound of a heavy fall behind him.  He turned and saw that one of his men was down.

He took a step forward, when the other pitched on his face.

Locke tried to rescue them, but by this time the deadly fumes had reached him and he, too, fell to the floor, coughing his life away.

At that moment Balcom got up from the divan and, stepping over Locke’s prostrate body, left the place, forgetting to close the door behind him.

When Zita telephoned Paul, Paul made an immediate appointment for her to meet him at Doctor Q’s, and when she arrived there Paul was already in conference with the doctor.

Over the telephone Zita had already given Paul a brief account of what had happened, and thus the two men were prepared with a plan when she arrived.

“Get Eva to the hypnotist’s on River Street,” instructed Doctor Q.  “Tell her that I have been hypnotized and that under the spell I will tell all.”

It was a desperate thing for Zita to attempt, after treating the Brents so shamelessly.  But there was no alternative.  For she knew well that, with Balcom, only a success would offset her miserable failure earlier in the evening.  Besides, were not her fortunes tied up with Balcom—­or perhaps with Paul?  She did not demur, but left immediately for Brent Rock to make the attempt, revolving in her mind how she was to do it.

Zita had difficulty in persuading Eva to see her at all, but, once she had succeeded, the possibility that all the mystery might be cleared up appealed strongly to Eva.  For Zita had framed her story cleverly and was playing desperately.

“Then I’ll meet you at the hypnotist’s in about half an hour,” agreed Eva, after Zita had told her how friendless she herself was and how both Balcom and Paul had refused her aid.

Zita left Brent Rock alone and was passing a dark corner when a hand reached out and grasped her by the arm and she heard a voice that she recognized.

“Your failure has made me redouble my efforts,” it hissed.  “I have just killed Locke in my apartment and I—­”

It was Balcom.  But Zita waited to hear no more.  Secretly she had always loved Locke.  Though she had worked against him, the very thought that he might be dead shocked her.  She tore herself from the grasp of Balcom before she could hear more and ran like a deer toward the apartment.

Fortunately, it was not far.  She tore up-stairs and through the door that Balcom had left open.

Everything was as Balcom had left it, except that now the three men lay quite still.  Zita staggered over to a window and threw it open.

Next she got water and extinguished the still smoldering powder.  Then, falling on her knees, she tried to help the stricken men.