Vic Marquette had revealed his identity to Professor Whitburn, as soon as the old man had recovered, the next morning.
The loss of the plans had been discovered.
Professor Whitburn had decided to rest from his labors. He had wired his sister to come and take care of his house, while he recuperated.
Harry Vincent and Arlette DeLand had remained as his guests. Now that the enemy had left, the island was a safe place for Arlette, and the best spot for Harry Vincent to recover from his injuries.
Marquette had taken charge of affairs long enough to arrange for one of the men from the village to take a job as handy man; and he had also obtained some other servants.
The house was transformed from an experimental laboratory to a country home.
But Marquette had left immediately afterward. He had received a message brought by Bruce Duncan. When he had read its contents, he had started immediately for New York, leaving Duncan to keep Harry Vincent company.
No one but the secret-service man knew the contents of that note. It had come, indirectly, from The Shadow, and it had proposed certain plans that pleased Vic Marquette.
The message had disclosed facts which the government man had not known; and he was raised from the depths of gloom. He had promised to cooperate by following the instructions which were given him.
It was now the night set for the Red meeting. A man, alone in a dark room, was working at a table above which hung a shaded lamp. His hands were sorting papers of various sorts, in an effort to find the solution to pressing perplexities.