The girl nodded.
“My father was an American,” she said. “He died in Russia. My mother, who was a Russian, brought me to New York to escape the revolution. Her health weakened and she went to California. I remained in New York, sending her most of the money that I earned.
“I met one of the Red agents. He promised me better work. It was not until I had accepted his offer that I realized how insidious it was. I could not turn back; but, to protect myself, I tried to learn the identities of the other agents.
“Volovick was one. I used to go to the Pink Rat to report. One night I saw the proprietor open the secret panel. The night you were in danger, I led you there. I came back later, but you were gone. I had been instructed to watch Bruce Duncan, to whom I had been introduced on the boat. I purposely neglected my duty to let him leave New York unfollowed.
“I followed a Red Agent who called himself Ernest Manion. He watched you at the Metrolite Hotel. I overheard him repeating instructions on the telephone. I warned you. When I knew the attack was to begin, I came here.”
Professor Whitburn appeared. He held a telegram.
“Crawford will be here to-night,” he said. “I mean Marquette not Crawford. He is bringing my plans. My invention is saved for the United States government!”
Harry gave his congratulations. When he turned to speak to Arlette, the girl was gone.
Bruce Duncan appeared an hour later. He handed Harry an envelope.
“I met Arlette DeLand in the village,” he explained. “She asked me to give you this.”