For the moment memory rose up so strong within her, that she could almost have fancied she heard again the struggle going on in the drawing-room, and that she saw once more, in the moonlight, the blood-stained hand which she now knew to have been that of Jack Rotherfield.

The idea seized her that now she would find him involved in a fresh mystery, and recoiling from a possible discovery, she had turned, almost resolved to creep back to her room and give up her expedition, when the sound of a key turned in a lock struck her ear.

There was something going on, something wrong. For Sir Robert’s sake she must conquer her repugnance, and find out what it was. She almost prayed that she might find that a burglar had got into the house, but she knew that the solution of the mystery would be something more unpleasant than that.

Hurriedly reaching the bottom of the staircase, she turned in the direction of the gallery. She had to pass through Sir Robert’s study, and the door of this room she found suspiciously left open. So too was the door beyond, which led into the little passage at the end of which was the door leading into the gallery.

As she entered the study, and made her way across to the opposite door, she became aware of a tell-tale sound: it was a whisper. She could not hear any words: she could not distinguish the voice; but the fact was conclusive: since some one whispered, there must be some one to whisper to; there were at least two persons somewhere close by, and Rhoda had no difficulty in making a guess who those two persons were.

And, remembering the disappearance of the snuff-boxes, she could have little doubt as to the sort of errand which had taken them to Sir Robert’s gallery.

Lady Sarah had robbed her husband before, she had now apparently taken an accomplice to help her to rob him again.

This was the thought in Rhoda’s mind, as, full of indignation, and regardless of the consequences to herself, she crossed the floor of the study, and groped her way into the passage beyond.

There was no light there, and she presently hesitated, filled with the uncanny fear none of us can help in the dark, in the presence of some one whom we cannot see, but who, we have reason to think, may be able to see us.

For, compared with the pitchy blackness of the passage into which she was stepping, the study behind her was light.