d a
moment before denied. Foyle's foot pressed heavily on the toe of the
baronet to warn him not to speak.

"Yes, it was for Sir Ralph," he said. "That is why I brought him here.
It is you, though, who hold the key to this mystery. We know that you
would have sent your jewels to Grell, that you are in communication with
his friends. You are young, Lady Eileen, and don't realise that you are
playing with fire. Your silence can do your lover no good--it may do him
and yourself harm. You have been visited by the Princess Petrovska, an
adventuress not fit to touch the hem of your skirt. You are already
involved. Take the advice of a man old enough to be your father, and
confide in us."

She had risen, and her slim form towered over the seated detective. She
seemed about to resent his words, but suddenly burst into a ripple of
laughter.

"You would be offensive if you were not amusing, Mr. Foyle. Don't you
think my help would be a little superfluous, since you know so much?"
she asked with a quietness that robbed the remark of some of its
bitterness. "I think you had better go now."

"I am sorry," said Foyle. "You may regret that you did not take my
advice."

She herself held the door open for them to pass out. To the surprise of
Fairfield, she held out her hand to him while ignoring the detective.

"Come back alone as soon as you can," she whispered. "I want to speak to
you."

Foyle had apparently neither heeded nor heard. Yet, as soon as they were
out of eye-shot of the house, he turned to Fairfield.

"She asked you to go back?"

"Eh?" The baronet was startled. "Yes. How did you know? Did you overhear
her?"

"No, but I hoped she would when I took you there. That was the whole
reason of our visit. I didn't expect to get her to say or admit
anything."

Fairfield came to an abrupt halt and gripped his companion by the arm.

"You intended-- For what reason? How could you know?"

"Absolute common sense, my dear sir. That's all. Absolute common sense.
If you are a chess-player, you know that the man who can foretell what
move his opponent is going to make usually wins. Here, let's find a
quiet Piccadilly tea-shop and I'll tell you all about it."

There is no place which one may find more convenient for a quiet
conversation than the London tea-shop before twelve in the morning. Over
a cup of coffee in the deserted smoking-room Foyle spoke to the point.

"I did not tell you why I took you to see Lady Eileen, be