must have had him
under his thumb in some way. Why did I not know of this before? It's clear
enough now. Thalassa, even if he did not commit the murder--"

"He did not," she said quickly. "He left the house with me, so he could
not have done it."

"Then he knows who did. He and your father shared some secret
together--some dreadful secret which brought about your father's death.
That is one reason why Thalassa will not speak--because he is implicated
in this mystery, whatever it is."

"No, no. He is keeping silence because of me--I feel sure. I made him
promise not to tell."

Charles Turold shook his head decidedly. "He may have more than one reason
for keeping silent," he said with a swift flash of intuition. "If it is as
you say, he is shielding himself as well as you. If your father was killed
while Thalassa was out of the house that night, Thalassa knows who did
it."

Her eyes met his in an agony of perplexity and distress. "Oh, no, I cannot
think you are right," she said. "If I could only see Thalassa--for five
minutes--"

"What good would that do?" he abruptly demanded.

"He would tell me the truth--if he knew."

He shook his head incredulously. "You do not know all," he murmured. He
shrank from telling her of the marks on her father's arm. "I know
Thalassa," she eagerly replied. "He would tell me if he thought it would
help me."

"If you think that I will go down and see him--and get it all out of him."

"No, no! You must not go," she cried in affright. "It would not be safe
for you."

"Would it be any more dangerous than hiding in London like a skulking
rat?" he bitterly replied. "This cannot go on. We are both in a dangerous
position, and might be arrested at any moment. What would happen then? Who
would believe my story--or yours? They sound improbable even to ourselves.
Here, at least, is a chance of discovering the truth, for I most solemnly
believe that Thalassa knows it, or guesses it. What other chance have we
of finding out the hideous mystery of that night? I must go, Sisily. I
will be careful, for your sake."

She knew by his voice that he was not to be deterred from the hazardous
enterprise, so she did not attempt to dissuade him further. But she clung
to him trembling, as though she would have shielded him from the menace of
capture. He was thinking rapidly.

"It may be that I shall fail," he said. "I do not think so, because I
shall take every precaution, but the police will be wat