Don't you see the situation?
She must have had knowledge that Whitmore was coming back.

And, isn't it more than likely that before she consented to return to her husband she exacted a promise from him not to execute the vengeance which he had threatened ?" "It's certainly an amazing tangle," admitted Greig.

"And I had thought that it was all clear as day!" "No, Greig," smiled Britz, "it isn't very likely that we're going to arrest Collins.

But we'll go to the woman's house and watch developments." The two detectives proceeded uptown in the subway to Ninety-first street, then walked slowly down Broadway, turning west at Ninetieth street.
As they turned the corner they became aware of an excited group of men and women in front of a big, gray-stone house, the name of which corresponded to that given by the visitor at Headquarters.
The crowd was gathered in front of the entrance, talking excitedly, each asking the other what had happened.

No one seemed to know precisely what the excitement was about, but that something extraordinary had occurred was plainly evident.
Britz and Greig plunged into the hallway and pushed the elevator button, but the car did not descend.