"This is strange," said Gertrude at last. "Newton must be very ill—or something." She arose. "I wonder if we'd better investigate. I hate to intrude, but we ought to be getting back, I didn't tell anybody at home where I was going."
"Nor I—I didn't tell anybody," said Mary. "I thought we should be back long ago. Yes, let us find someone."
They went on through the open door into a bedroom. Out of this opened a small dining room, and beyond that a little kitchen. There was a tiny bathroom, and lights were burning in all the rooms. But there was no sign of the sick man.
They looked at one another, puzzled and anxious.
"They seem to have gone out," said Mary. "Here is another bedroom. Perhaps Fitzgerald is here."
But the bed, all clean and white, had not been disturbed.
Simultaneously, they turned and went back to the door by which they had entered the flat. It was locked.
"We've been trapped," said Gertrude in a low voice. "Let's look through the place."
They began another search, opening closet doors and looking into wardrobes and cupboards and under the furniture. They went to the kitchen and tried the door into the back passage; but that, too, was locked. There was nobody else in the flat; there was no possible way of getting out.
"The windows," said Gertrude. "There should be fire escapes."