This aspect of the case struck Barrant as very strange and deep, because it failed to account for Sisily's subsequent flight.

If Thalassa had jeopardized himself by keeping silence about her visit, and had returned the key to her father's room in order to create the idea of suicide, why had she dispelled the illusion by running away, bringing both her accomplice and herself into danger?
Had she been, seized with terror, perhaps due to Mrs.Pendleton's insistence on her belief of murder, or had Thalassa conveyed some warning to her that inquiries were likely to be put afoot?
These were questions to which Barrant felt he could find no answer until he had seen Thalassa and attempted to wrest the truth from him.
He postponed his visit to Hint House until the evening.

He wanted to make the journey as Sisily had made it on the previous night, in order to find out, as nearly as possible, the exact moment she had arrived at her father's house.

He was not even in a position to prove that she had gone by the wagonette until he had questioned the driver.
He took his way to the station that evening with the feeling that it would be difficult to get anything out of Thalassa, whatever the reasons for his silence.

He instinctively recognized that the authority of the law, which strikes such terror into craven hearts, would not help him with this old man whose glance had the lawless fearlessness of an eagle.